remarkable for the gentleness of its current that it was specially
noticed by Catullus as flowing _molli flumine_--deserves more than a
passing remark. This river rises in the mountain chain east of Lake
Iseo, and traversing the district of Brescia, empties into the Oglio
after a course of about seventy miles. The iron works in the upper
valley of the Mella had long created a considerable demand for wood, but
their operations were not so extensive as to occasion any very sudden or
general destruction of the forests, and the only evil experienced from
the clearings was the gradual diminution of the volume of the river.
Within the last twenty years, the superior quality of the arms
manufactured at Brescia has greatly enlarged the sale of them, and very
naturally stimulated the activity of both the forges and of the colliers
who supply them, and the hillsides have been rapidly stripped of their
timber. Up to 1850, no destructive inundation of the Mella had been
recorded. Buildings in great numbers had been erected upon its margin,
and its valley was conspicuous for its rural beauty and its fertility.
But when the denudation of the mountains had reached a certain point,
avenging nature began the work of retribution. In the spring and summer
of 1850 several new torrents were suddenly formed in the upper tributary
valleys, and on the 14th and 15th of August in that year, a fall of
rain, not heavier than had been often experienced, produced a flood
which not only inundated much ground never before overflowed, but
destroyed a great number of bridges, dams, factories, and other valuable
structures, and, what was a far more serious evil, swept off from the
rocks an incredible extent of soil, and converted one of the most
beautiful valleys of the Italian Alps into a ravine almost as bare and
as barren as the savagest gorge of Southern France. The pecuniary damage
was estimated at many millions of francs, and the violence of the
catastrophe was deemed so extraordinary, even in a country subject to
similar visitations, that the sympathy excited for the sufferers
produced, in five months, voluntary contributions for their relief to
the amount of nearly $200,000--_Delle Inondazioni del Mella, etc., nella
notte del 14 al 15 Agosto_, 1850.
The author of this remarkable pamphlet has chosen as a motto a passage
from the Vulgate translation of Job, which is interesting as showing
accurate observation of the action of the torrent: "Mons cadens definit,
et saxum transfertur de loco suo; lapides excavant aquae et alluvione
paullatim terra consumitur."--_Job_ xiv, 18, 19.
The English version is much less striking, and gives a different sense.
[223] Streffleur quotes from Duile the following observations: "The
channel of the Tyrolese brooks is often raised much above the valleys
through which they flow. The bed of the Fersina is elevated high above
the city of Trient, which lies near it. The Villerbach flows at a much
more elevated level than that of the market place of Neumarkt and Vill,
and threatens to overwhelm both of them with its waters. The Talfer at
Botzen is at least even with the roofs of the adjacent town, if not
above them. The tower steeples of the villages of Schlanders, Kortsch,
and Laas, are lower than the surface of the Gadribach. The Saldurbach at
Schluderns menaces the far lower village with destruction, and the chief
town, Schwaz, is in similar danger from the Lahnbach."--STREFFLEUR,
_Ueber die Wildbaeche, etc._, p. 7.
[224] The snow drifts into the ravines and accumulates to incredible
depths, and the water resulting from its dissolution and from the
deluging rains which fall in spring, and sometimes in the summer, being
confined by rocky walls on both sides, rises to a very great height, and
of course acquires an immense velocity and transporting power in its
rapid descent to its outlet from the mountain. In the winter of
1842--'3, the valley of the Doveria, along which the Simplon road
passes, was filled with solid snowdrifts to the depth of a hundred feet
above the carriage road, and the sledge track by which passengers and
the mails were carried ran at that height.
Other things being equal, the transporting power of the water is
greatest where its flow is most rapid. This is usually in the direction
of the axis of the ravine. As the current pours out of the gorge and
escapes from the lateral confinement of its walls, it spreads and
divides itself into numerous smaller streams, which shoot out from the
mouth of the valley, as from a centre, in different directions, like the
ribs of a fan from the pivot, each carrying with it its quota of stones
and gravel. The plain below the point of issue from the mountain is
rapidly raised by newly formed torrents, the elevation depending on the
inclination of the bed and the form and weight of the matter
transported. Every flood both increases the height of this central point
and extends the entire circumference of the deposit. The stream
retaining most nearly the original direction moves with the greatest
momentum, and consequently transports the solid matter with which it is
charged to the greatest distance.
The untravelled reader will comprehend this the better when he is
informed that the southern slope of the Alps generally rises suddenly
out of the plain, with no intervening hill to break the abruptness of
the transition, except those consisting of comparatively small heaps of
its own debris brought down by ancient glaciers or recent torrents. The
torrents do not wind down valleys gradually widening to the rivers or
the sea, but leap at once from the flanks of the mountains upon the
plains below. This arrangement of surfaces naturally facilitates the
formation of vast deposits at their points of emergence, and the centre
of the accumulation in the case of very small torrents is not
unfrequently a hundred feet high, and sometimes very much more.
Torrents and the rivers that receive them transport mountain debris to
almost incredible distances. Lorentz, in an official report on this
subject, as quoted by Marschand from the Memoirs of the Agricultural
Society of Lyons, says: "The felling of the woods produces torrents
which cover the cultivated soil with pebbles and fragments of rock, and
they do not confine their ravages to the vicinity of the mountains, but
extend them into the fertile fields of Provence and other departments,
to the distance of forty or fifty leagues."--_Entwaldung der Gebirge_,
p. 17.
[225] The precipitous walls of the Val de Lys, and more especially of
the Val Doveria, though here and there shattered, show in many places a
smoothness of face over a large vertical plane, at the height of
hundreds of feet above the bottom of the valley, which no known agency
but glacier ice is capable of producing, and of course they can have
undergone no sensible change at those points for a vast length of time.
The beds of the rivers which flow through those valleys suffer lateral
displacement occasionally, where there is room for the shifting of the
channel; but if any elevation or depression takes place in them, it is
too slow to be perceptible except in case of some merely temporary
obstruction.
[226] Lombardini found, twenty years ago, that the mineral matter
brought down to the Po by its tributaries was, in general, comminuted to
about the same degree of fineness as the sands of its bed at their
points of discharge. In the case of the Trebbia, which rises high in the
Apennines and empties into the Po at Piacenza, it was otherwise, that
river rolling pebbles and coarse gravel into the channel of the
principal stream. The banks of the other affluents--excepting some of
those which discharge their waters into the great lakes--then either
retained their woods, or had been so long clear of them, that the
torrents had removed most of the disintegrated and loose rock in their
upper basins. The valley of the Trebbia had been recently cleared, and
all the forces which tend to the degradation and transportation of rock
were in full activity.--_Notice sur les Rivieres de la Lombardie,
Annales des Ponts et Chaussees_, 1847, 1er semestre, p. 131.
Since the date of Lombardini's observations, many Alpine valleys have
been stripped of their woods. It would be interesting to know whether
any sensible change has been produced in the character or quantity of
the matter transported by them to the Po.
[227] In proportion as the dikes are improved, and breaches and the
escape of the water through them are less frequent, the height of the
annual inundations is increased. Many towns on the banks of the river,
and of course within the system of parallel embankments, were formerly
secure from flood by the height of the artificial mounds on which they
were built; but they have recently been obliged to construct ring dikes
for their protection.--BAUMGARTEN, after LOMBARDINI, in the paper last
quoted, pp. 141, 147.
[228] Three centuries ago, when the declivities of the mountains still
retained a much larger proportion of their woods, the moderate annual
floods of the Po were occasioned by the melting of the snows, and, as
appears by a passage of Tasso quoted by Castellani (_Dell' Influenza
delle Selve_, i, p. 58, note), they took place in May. The much more
violent inundations of the present century are due to rains, the waters
of which are no longer retained by a forest soil, but conveyed at once
to the rivers--and they occur almost uniformly in the autumn or late
summer. Castellani, on the page just quoted, says that even so late as
about 1780, the Po required a heavy rain of a week to overflow its
banks, but that forty years later, it was sometimes raised to full flood
in a single day.
[229] This change of coast line cannot be ascribed to upheaval, for a
comparison of the level of old buildings--as, for instance, the church
of San Vitale and the tomb of Theodoric at Ravenna--with that of the
sea, tends to prove a depression rather than an elevation of their
foundations.
A computation by a different method makes the deposits at the mouth of
the Po 2,123,000 metres less; but as both of them omit the gravel and
silt rolled, if not floated, down at ordinary and low water, we are safe
in assuming the larger quantity.--_Article last quoted_, p. 174. (See
note, p. 329)
[230] Mengotti estimated the mass of solid matter annually "united to
the waters of the Po" at 822,000,000 cubic metres, or nearly twenty
times as much as, according to Lombardini, that river delivers into the
Adriatic. Castellani supposes the computation of Mengotti to fall much
below the truth, and there can be no doubt that a vastly larger quantity
of earth and gravel is washed down from the Alps and the Apennines than
is carried to the sea.--CASTELLANI, _Dell' Immediata Influenza delle
Selve sul corso delle Acque_, i, pp. 42, 43.
I have contented myself with assuming less than one fifth of Mengotti's
estimate.
[231] BAUMGARTEN, _An. des Ponts et Chaussees_, 1847, 1er semestre, p.
175.
[232] The total superficies of the basin of the Po, down to Ponte
Lagoscuro [Ferrara]--a point where it has received all its affluents--is
6,938,200 hectares, that is, 4,105,600 in mountain lands, 2,832,600 in
plain lands.--DUMONT, _Travaux Publics, etc._, p. 272.
These latter two quantities are equal respectively to 10,145,348, and
6,999,638 acres, or 15,852 and 10,937 square miles.
[233] I do not use the numbers I have borrowed or assumed as factors the
value of which is precisely ascertained; nor, for the purposes of the
present argument, is quantitative exactness important. I employ
numerical statements simply as a means of aiding the imagination to form
a general and certainly not extravagant idea of the extent of
geographical revolutions which man has done much to accelerate, if not,
strictly speaking, to produce.
There is an old proverb, _Dolus latet in generalibus_, and Arthur Young
is not the only public economist who has warned his readers against the
deceitfulness of round numbers. I think, on the contrary, that vastly
more error has been produced by the affectation of precision in cases
where precision is impossible. In all the great operations of
terrestrial nature, the elements are so numerous and so difficult of
exact appreciation, that, until the means of scientific observation and
measurement are much more perfected than they now are, we must content
ourselves with general approximations. I say _terrestrial_ nature,
because in cosmical movements we have fewer elements to deal with, and
may therefore arrive at much more rigorous accuracy in determination of
time and place than we can in fixing and predicting the quantities and
the epochs of variable natural phenomena on the earth's surface.
The value of a high standard of accuracy in scientific observation can
hardly be overrated; but habits of rigorous exactness will never be
formed by an investigator who allows himself to trust implicitly to the
numerical precision of the results of a few experiments. The wonderful
accuracy of geodetic measurements in modern times is, in general,
attained by taking the mean of a great number of observations at every
station, and this final precision is but the mutual balance and
compensation of numerous errors.
Travellers are often misled by local habits in the use of what may be
called representative numbers, where a definite is put for an indefinite
quantity. A Greek, who wished to express the notion of a great, but
undetermined number, used "myriad, or ten thousand;" a Roman, "six
hundred;" an Oriental, "forty," or, at present, very commonly, "fifteen
thousand." Many a tourist has gravely repeated, as an ascertained fact,
the vague statement of the Arabs and the monks of Mount Sinai, that the
ascent from the convent of St. Catherine to the summit of Gebel Moosa
counts "fifteen thousand" steps, though the difference of level is
barely two thousand feet, and the "Forty" Thieves, the "forty" martyr
monks of the convent of El Arbain--not to speak of a similar use of this
numeral in more important cases--have often been understood as
expressions of a known number, when in fact they mean simply _many_. The
number "fifteen thousand" has found its way to Rome, and De Quincey
seriously informs us, on the authority of a lady who had been at much
pains to ascertain the _exact_ truth, that, including closets large
enough for a bed, the Vatican contains fifteen thousand rooms. Any one
who has observed the vast dimensions of most of the apartments of that
structure will admit that we make a very small allowance of space when
we assign a square rod, sixteen and a half feet square, to each room
upon the average. On an acre, there might be one hundred and sixty such
rooms, including partition walls; and, to contain fifteen thousand of
them, a building must cover more than nine acres, and be ten stories
high, or possess other equivalent dimensions, which, as every traveller
knows, many times exceeds the truth.
That most entertaining writer, About, reduces the number of rooms in the
Vatican, but he compensates this reduction by increased dimensions, for
he uses the word _salle_, which cannot be applied to closets barely
large enough to contain a bed. According to him, there are in that
"presbytere," as he irreverently calls it, twelve thousand large rooms
[_salles_], thirty courts, and three hundred staircases.--_Rome
Contemporaire_, p. 68.
The pretended exactness of statistical tables is generally little better
than an imposture; and those founded not on direct estimation by
competent observers, but on the report of persons who have no particular
interest in knowing, but often have a motive for distorting, the
truth--such as census returns--are commonly to be regarded as but vague
guesses at the actual fact.
Fuller, who, for the combination of wit, wisdom, fancy, and personal
goodness, stands first in English literature, thus remarks on the
pretentious exactness of historical and statistical writers: "I approve
the plain, country By-word, as containing much Innocent Simplicity
therein,
_'Almost and very nigh
Have saved many a Lie.'_
So have the Latines their _prope_, _fere_, _juxta_, _circiter_, _plus
minus_, used in matters of fact by the most authentic Historians. Yea,
we may observe that the Spirit of Truth itself, where _Numbers_ and
_Measures_ are concerned, in Times, Places, and Persons, useth the
aforesaid Modifications, save in such cases where some mystery contained
in the number requireth a particular specification thereof:
In Times. | In Places. | In Person.
| |
Daniel, 5:33. | Luke, 24:13. | Exodus, 12:37.
Luke, 3:23. | John, 6:19. | Acts, 2:41.
None therefore can justly find fault with me, if, on the like occasion,
I have secured myself with the same Qualifications. Indeed, such
Historians who grind their Intelligence to the _powder of fraction_,
pretending to _cleave the pin_, do sometimes _misse the But_. Thus, one
reporteth, how in the Persecution under _Dioeletian_, there were neither
under nor over, but just _nine hundred ninety-nine_ martyrs. Yea,
generally those that trade in such _Retail-ware_, and deal in such small
parcells, may by the ignorant be commended for their _care_, but
condemned by the judicious for their ridiculous _curiosity_."--_The
History of the Worthies of England_, i, p. 59.
[234] SURELL, _Les Torrents des Hautes Alpes_, chap. xxiv. In such
cases, the clearing of the ground, which, in consequence of a temporary
diversion of the waters, or from some other cause, has become rewooded,
sometimes renews the ravages of the torrent. Thus, on the left bank of
the Durance, a wooded declivity had been formed by the debris brought
down by torrents, which had extinguished themselves after having swept
off much of the superficial strata of the mountain of Morgon. "All this
district was covered with woods, which have now been thinned out and are
perishing from day to day; consequently, the torrents have recommenced
their devastations, and if the clearings continue, this declivity, now
fertile, will be ruined, like so many others."--Id., p. 155.
[235] Where a torrent has not been long in operation, and earth still
remains mixed with the rocks and gravel it heaps up at its point of
eruption, vegetation soon starts up and prospers, if protected from
encroachment. In Provence, "several communes determined, about ten years
ago, to reserve the soils thus wasted, that is, to abandon them for a
certain time, to spontaneous vegetation, which was not slow in making
its appearance."--BECQUEREL, _Des Climats_, p. 315.
[236] Rock is permeable by water to a greater extent than is generally
supposed. Freshly quarried marble, and even granite, as well as most
other stones, are sensibly heavier, as well as softer and more easily
wrought, than after they are dried and hardened by air-seasoning. Many
sandstones are porous enough to serve as filters for liquids, and much
of that of Upper Egypt and Nubia hisses audibly when thrown into water,
from the escape of the air forced out of it by hydrostatic pressure and
the capillary attraction of the pores for water. See _Appendix_, No. 29.
[237] Palissy had observed the action of frost in disintegrating rock,
and he thus describes it, in his essay on the formation of ice: "I know
that the stones of the mountains of Ardennes be harder than marble.
Nevertheless, the people of that country do not quarry the said stones
in winter, for that they be subject to frost; and many times the rocks
have been seen to fall without being cut, by means whereof many people
have been killed, when the said rocks were thawing." Palissy was
ignorant of the expansion of water in freezing--in fact he supposed that
the mechanical force exerted by freezing water was due to compression,
not dilatation--and therefore he ascribes to thawing alone effects
resulting not less from congelation.
Various forces combine to produce the stone avalanches of the higher
Alps, the fall of which is one of the greatest dangers incurred by the
adventurous explorers of those regions--the direct action of the sun
upon the stone, the expansion of freezing water, and the loosening of
masses of rock by the thawing of the ice which supported them or held
them together.
[238] WESSELY, _Die Oesterreichischen Alpenlaender und ihre Forste_, pp.
125, 126. Wessely records several other more or less similar occurrences
in the Austrian Alps. Some of them, certainly, are not to be ascribed to
the removal of the woods, but in most cases they are clearly traceable
to that cause.
[239] BIANCHI, Appendix to the Italian translation of Mrs. SOMERVILLE's
_Physical Geography_, p. xxxvi.
[240] See in KOHL, _Alpenreisen_, i, 120, an account of the ruin of
fields and pastures, and even of the destruction of a broad belt of
forest, by the fall of rocks in consequence of cutting a few large
trees. Cattle are very often killed in Switzerland by rock avalanches,
and their owners secure themselves from loss by insurance against this
risk as against damage by fire or hail.
[241] _Entwaldung der Gebirge_, p. 41.
[242] The importance of the wood in preventing avalanches is well
illustrated by the fact that, where the forest is wanting, the
inhabitants of localities exposed to snow slides often supply the place
of the trees by driving stakes through the snow into the ground, and
thus checking its propensity to slip. The woods themselves are sometimes
thus protected against avalanches originating on slopes above them, and
as a further security, small trees are cut down along the upper line of
the forest, and laid against the trunks of larger trees, transversely to
the path of the slide, to serve as a fence or dam to the motion of an
incipient avalanche, which may by this means be arrested before it
acquires a destructive velocity and force.
[243] The tide rises at Quebec to the height of twenty-five feet, and
when it is aided by a northeast wind, it flows with almost irresistible
violence. Rafts containing several hundred thousand cubic feet of timber
are often caught by the flood tide, torn to pieces, and dispersed for
miles along the shores.
[244] One of these, the Baron of Renfrew--so named from one of the
titles of the kings of England--built thirty or forty years ago,
measured 5,000 tons. They were little else than rafts, being almost
solid masses of timber designed to be taken to pieces and sold as lumber
on arriving at their port of destination.
The lumber trade at Quebec is still very large. According to a recent
article in the _Revue des Deux Mondes_, that city exported, in 1860,
30,000,000 cubic feet of squared timber, and 400,000,000 square feet of
"planches." The thickness of the boards is not stated, but I believe
they are generally cut an inch and a quarter thick for the Quebec trade,
and as they shrink somewhat in drying, we may estimate ten square for
one cubic foot of boards. This gives a total of 70,000,000 cubic feet.
The specific gravity of white pine is .554, and the weight of this
quantity of lumber, very little of which is thoroughly seasoned, would
exceed a million of tons, even supposing it to consist wholly of wood as
light as pine. New Brunswick, too, exports a large amount of lumber.
[245] This name, from the French _chantier_, which has a wider meaning,
is applied in America to temporary huts or habitations erected for the
convenience of forest life, or in connection with works of material
improvement.
[246] Trees differ much in their power of resisting the action of forest
fires. Different woods vary greatly in combustibility, and even when
their bark is scarcely scorched, they are, partly in consequence of
physiological character, and partly from the greater or less depth at
which their roots habitually lie below the surface, very differently
affected by running fires. The white pine, _Pinus strobus_, as it is the
most valuable, is also perhaps the most delicate tree of the American
forest, while its congener, the Northern pitch pine, _Pinus rigida_, is
less injured by fire than any other tree of that country. I have heard
experienced lumbermen maintain that the growth of this pine was even
accelerated by a fire brisk enough to destroy all other trees, and I
have myself seen it still flourishing after a conflagration which had
left not a green leaf but its own in the wood, and actually throwing out
fresh foliage, when the old had been quite burnt off and the bark almost
converted into charcoal. The wood of the pitch pine is of comparatively
little value for the joiner, but it is useful for very many purposes.
Its rapidity of growth in even poor soils, its hardihood, and its
abundant yield of resinous products, entitle it to much more
consideration, as a plantation tree, than it has hitherto received in
Europe or America.
[247] Between fifty and sixty years ago, a steep mountain with which I
am very familiar, composed of metamorphic rock, and at that time covered
with a thick coating of soil and a dense primeval forest, was
accidentally burnt over. The fire took place in a very dry season, the
slope of the mountain was too rapid to retain much water, and the
conflagration was of an extraordinarily fierce character, consuming the
wood almost entirely, burning the leaves and combustible portion of the
mould, and in many places cracking and disintegrating the rock beneath.
The rains of the following autumn carried off much of the remaining
soil, and the mountain side was nearly bare of wood for two or three
years afterward. At length, a new crop of trees sprang up and grew
vigorously, and the mountain is now thickly covered again. But the depth
of mould and earth is too small to allow the trees to reach maturity.
When they attain to the diameter of about six inches, they uniformly
die, and this they will no doubt continue to do until the decay of
leaves and wood on the surface, and the decomposition of the subjacent
rock, shall have formed, perhaps hundreds of years hence, a stratum of
soil thick enough to support a full-grown forest.
[248] The growth of the white pine, on a good soil and in open ground,
is rather rapid until it reaches the diameter of a couple of feet, after
which it is much slower. The favorite habitat of this tree is light
sandy earth. On this soil, and in a dense wood, it requires a century to
attain the diameter of a yard. Emerson (_Trees of Massachusetts_, p.
65), says that a pine of this species, near Paris, "thirty years
planted, is eighty feet high, with a diameter of three feet." He also
states that ten white pines planted at Cambridge, Massachusetts, in 1809
or 1810, exhibited, in the winter of 1841 and 1842, an average of twenty
inches diameter at the ground, the two largest measuring, at the height
of three feet, four feet eight inches in circumference; and he mentions
another pine growing in a rocky swamp, which, at the age of thirty-two
years, "gave seven feet in circumference at the but, with a height of
sixty-two feet six inches." This latter I suppose to be a seedling, the
others _transplanted_ trees, which might have been some years old when
placed where they finally grew.
The following case came under my own observation: In 1824, a pine tree,
so small that a young lady, with the help of a lad, took it up from the
ground and carried it a quarter of a mile, was planted near a house in a
town in Vermont. It was occasionally watered, but received no other
special treatment. I measured this tree in 1860, and found it, at four
feet from the ground, and entirely above the spread of the roots, two
feet and four inches in diameter. It could not have been more than three
inches through when transplanted, and must have increased its diameter
twenty-five inches in thirty-six years.
[249] WILLIAMS, _History of Vermont_, ii, p. 53. DWIGHT's _Travels_, iv,
p. 21, and iii, p. 36. EMERSON, _Trees of Massachusetts_, p. 61. PARISH,
_Life of President Wheelock_, p. 56.
[250] The forest trees of the Northern States do not attain to extreme
longevity in the dense woods. Dr. Williams found that none of the huge
pines, the age of which he ascertained, exceeded three hundred and fifty
or four hundred years, though he quotes a friend who thought he had
noticed trees considerably older. The oak lives longer than the pine,
and the hemlock spruce is perhaps equally long lived. A tree of this
latter species, cut within my knowledge in a thick wood, counted four
hundred and eighty-six, or, according to another observer, five hundred
annual circles.
Great luxuriance of animal and vegetable production is not commonly
accompanied by long duration of the individual. The oldest men are not
found in the crowded city; and in the tropics, where life is prolific
and precocious, it is also short. The most ancient forest trees of which
we have accounts have not been those growing in thick woods, but
isolated specimens, with no taller neighbor to intercept the light and
heat and air, and no rival to share the nutriment afforded by the soil.
The more rapid growth and greater dimensions of trees standing near the
boundary of the forest, are matters of familiar observation. "Long
experience has shown that trees growing on the confines of the wood may
be cut at sixty years of age as advantageously as others of the same
species, reared in the depth of the forest, at a hundred and twenty. We
have often remarked, in our Alps, that the trunk of trees upon the
border of a grove is most developed or enlarged upon the outer or open
side, where the branches extend themselves farthest, while the
concentric circles of growth are most uniform in those entirely
surrounded by other trees, or standing entirely alone."--A. and G.
VILLA, _Necessita dei Boschi_, pp. 17, 18.
[251] Caimi states that "a single flotation in the Valtelline in 1839,
caused damages alleged to amount to more than $800,000, and actually
appraised at $250,000."--_Cenni sulla Importanza e Coltura dei Boschi_,
p. 65.
[252] Most physicists who have investigated the laws of natural
hydraulics maintain that, in consequence of direct obstruction and
frictional resistance to the flow of the water of rivers along their
banks, there is both an increased rapidity of current and an elevation
of the water in the middle of the channel, so that a river presents
always a convex surface. The lumbermen deny this. They affirm that,
while rivers are rising, the water is highest in the middle of the
channel, and tends to throw floating objects shoreward; while they are
falling, it is lowest in the middle, and floating objects incline toward
the centre. Logs, they say, rolled into the water during the rise, are
very apt to lodge on the banks, while those set afloat during the
falling of the waters keep in the current, and are carried without
hindrance to their destination.
Foresters and lumbermen, like sailors and other persons whose daily
occupations bring them into contact, and often, into conflict, with
great natural forces, have many peculiar opinions, not to say
superstitions. In one of these categories we must rank the universal
belief of lumbermen, that with a given head of water, and in a given
number of hours, a sawmill cuts more lumber by night than by day. Having
been personally interested in several sawmills, I have frequently
conversed with sawyers on this subject, and have always been assured by
them that their uniform experience established the fact that, other
things being equal, the action of the machinery of sawmills is more
rapid by night than by day. I am sorry--perhaps I ought to be
ashamed--to say that my scepticism has been too strong to allow me to
avail myself of my opportunities of testing this question by passing a
night, watch in hand, counting the strokes of a millsaw. More
unprejudiced, and I must add, very intelligent and credible persons have
informed me that they have done so, and found the report of the sawyers
abundantly confirmed. A land surveyor, who was also an experienced
lumberman, sawyer, and machinist, a good mathematician and an exact
observer, has repeatedly told me, that he had very often "timed"
sawmills, and found the difference in favor of night work above thirty
per cent. _Sed quaere._
[253] For many instances of this sort, see BECQUEREL, _Des Climats,
etc._, pp. 301-303. In 1664, the Swedes made an incursion into Jutland
and felled a considerable extent of forest. After they retired, a survey
of the damage was had, and the report is still extant. The number of
trees cut was found to be 120,000, and as an account was kept of the
numbers of each species of tree, the document is of interest in the
history of the forest, as showing the relative proportions between the
different trees which composed the wood. See VAUPELL. _Boegens
Indvandring_, p. 35, and _Notes_, p. 55.
[254] Since writing this paragraph, I have fallen upon--and that in a
Spanish author--one of those odd coincidences of thought which every man
of miscellaneous reading so often meets with. Antonio Ponz (_Viage de
Espana_, i, prologo, p. lxiii), says: "Nor would this be so great an
evil, were not some of them declaimers against _trees_, thereby
proclaiming themselves, in some sort, enemies of the works of God, who
gave us the leafy abode of Paradise to dwell in, where we should be even
now sojourning, but for the first sin, which expelled us from it."
I do not know at what period the two Castiles were bared of their woods,
but the Spaniard's proverbial "hatred of a tree" is of long standing.
Herrera vigorously combats this foolish prejudice; and Ponz, in the
prologue to the ninth volume of his journey, says that many carried it
so far as wantonly to destroy the shade and ornamental trees planted by
the municipal authorities. "Trees," they contended, and still believe,
"breed birds, and birds eat up the grain." Our author argues against the
supposition of the "breeding of birds by trees," which, he says, is as
absurd as to believe that an elm tree can yield pears; and he charitably
suggests that the expression is, perhaps, a _maniere de dire_, a popular
phrase, signifying simply that trees harbor birds.
[255] Religious intolerance had produced similar effects in France
at an earlier period. "The revocation of the edict of Nantes and
the dragonnades occasioned the sale of the forests of the unhappy
Protestants, who fled to seek in foreign lands the liberty of
conscience which was refused to them in France. The forests were
soon felled by the purchasers, and the soil in part brought under
cultivation."'--BECQUEREL, _Des Climats, etc._, p. 303.
[256] The American reader must be reminded that, in the language of the
chase and of the English law, a "forest" is not necessarily a wood. Any
large extent of ground, withdrawn from cultivation, reserved for the
pleasures of the chase, and allowed to clothe itself with a spontaneous
growth, serving as what is technically called "cover" for wild animals,
is, in the dialects I have mentioned, a forest. When, therefore, the
Norman kings afforested the grounds referred to in the text, it is not
to be supposed that they planted them with trees, though the protection
afforded to them by the game laws would, if cattle had been kept out,
soon have converted them into real woods.
[257] _Histoire des Paysans_, ii, p. 190. The work of Bonnemere is of
great value to those who study the history of mediaeval Europe from a
desire to know its real character, and not in the hope of finding
apparent facts to sustain a false and dangerous theory. Bonnemere is one
of the few writers who, like Michelet, have been honest enough and bold
enough to speak the truth with regard to the relations between the
church and the people in the Middle Ages.
[258] It is painful to add that a similar outrage was perpetrated a very
few years ago, in one of the European states, by a prince of a family
now dethroned. In this case, however, the prince killed the trespasser
with his own hand, his sergeants refusing to execute his mandate.
[259] GUILLAUME DE NANGIS, as quoted in the notes to JOINVILLE,
_Nouvelle Collection des Memoires, etc._, par Michaud et Poujoulat,
premiere serie, i, p. 335.
Persons acquainted with the character and influence of the mediaeval
clergy will hardly need to be informed that the ten thousand livres
never found their way to the royal exchequer. It was easy to prove to
the simple-minded king that, as the profits of sin were a monopoly of
the church, he ought not to derive advantage from the commission of a
crime by one of his subjects; and the priests were cunning enough both
to secure to themselves the amount of the fine, and to extort from Louis
large additional grants to carry out the purposes to which they devoted
the money. "And though the king did take the moneys," says the
chronicler, "he put them not into his treasury, but turned them into
good works; for he builded therewith the maison-Dieu of Pontoise, and
endowed the same with rents and lands; also the schools and the
dormitory of the friars preachers of Paris, and the monastery of the
Minorite friars."
[260] _Histoire des Paysans_, ii, p. 200.
[261] The following details from Bonnemere will serve to give a more
complete idea of the vexatious and irritating nature of the game laws of
France. The officers of the chase went so far as to forbid the pulling
up of thistles and weeds, or the mowing of any unenclosed ground before
St. John's day [24th June], in order that the nests of game birds might
not be disturbed. It was unlawful to fence-in any grounds in the plains
where royal residences were situated; thorns were ordered to be planted
in all fields of wheat, barley, or oats, to prevent the use of ground
nets for catching the birds which consumed, or were believed to consume,
the grain, and it was forbidden to cut or pull stubble before the first
of October, lest the partridge and the quail might be deprived of their
cover. For destroying the eggs of the quail, a fine of one hundred
livres was imposed for the first offence, double that amount for the
second, and for the third the culprit was flogged and banished for five
years to a distance of six leagues from the forest.--_Histoire des
Paysans_, ii, p. 202, text and notes.
Neither these severe penalties, nor any provisions devised by the
ingenuity of modern legislation, have been able effectually to repress
poaching. "The game laws," says Clave, "have not delivered us from the
poachers, who kill twenty times as much game as the sportsmen. In the
forest of Fontainebleau, as in all those belonging to the state,
poaching is a very common and a very profitable offence. It is in vain
that the gamekeepers are on the alert night and day, they cannot prevent
it. Those who follow the trade begin by carefully studying the habits of
the game. They will lie motionless on the ground, by the roadside or in
thickets, for whole days, watching the paths most frequented by the
animals," &c.--_Revue des Deux Mondes_, Mai, 1863, p. 160.
The writer adds many details on this subject, and it appears that, as
there are "beggars on horseback" in South America, there are poachers in
carriages in France.
[262] "Whole trees were sacrificed for the most insignificant purposes;
the peasants would cut down two firs to make a single pair of wooden
shoes."--MICHELET, as quoted by CLAVE, _Etudes_, p. 24.
A similar wastefulness formerly prevailed in Russia, though not from the
same cause. In St. Pierre's time, the planks brought to St. Petersburg
were not sawn, but hewn with the axe, and a tree furnished but a single
plank.
[263] "A hundred and fifty paces from my house is a hill of drift sand,
on which stood a few scattered pines. _Pinus sylvestris_, and
_Sempervivum tectorum_ in abundance, _Statice armeria_, _Ammone
vernalis_, _Dianthus carthusianorum_, with other sand plants, were
growing there. I planted the hill with a few birches, and all the plants
I have mentioned completely disappeared, though there were many naked
spots of sand between the trees. It should be added, however, that the
hillock is more thickly wooded than before. * * * It seems then that
_Sempervivum tectorum_, &c., will not bear the neighborhood of the
birch, though growing well near the _Pinus sylvestris_. I have found the
large red variety of _Agaricus deliciosus_ only among the roots of the
pine; the greenish-blue _Agaricus deliciosus_ among alder roots, but not
near any other tree. Birds have their partialities among trees and
shrubs. The _Silviae_ prefer the _Pinus Larix_ to other trees. In my
garden this _Pinus_ is never without them, but I never saw a bird perch
on _Thuja occidenialis_ or _Juniperus sabina_, although the thick
foliage of these latter trees affords birds a better shelter than the
loose leafage of other trees. Not even a wren ever finds its way to one
of them. Perhaps the scent of the _Thuja_ and the _Juniperus_ is
offensive to them. I have spoiled one of my meadows by cutting away the
bushes. It formerly bore grass four feet high, because many
umbelliferous plants, such as _Heracleum spondylium_, _Spiraea ulmaria_,
_Laserpitium latifolia_, &c., grew in it. Under the shelter of the
bushes these plants ripened and bore seed, but they gradually
disappeared as the shrubs were extirpated, and the grass now does not
grow to the height of more than two feet, because it is no longer
obliged to keep pace with the umbellifera which flourished among it."
See a paper by J. G. BUeTTNER, of Kurland, in BERGHAUS' _Geographisches
Jahrbuch_, 1852, No. 4, pp. 14, 15.
These facts are interesting as illustrating the multitude of often
obscure conditions upon which the life or vigorous growth of smaller
organisms depends. Particular species of truffles and of mushrooms are
found associated with particular trees, without being, as is popularly
supposed, parasites deriving their nutriment from the dying or dead
roots of those trees. The success of Rousseau's experiments seem
decisive on this point, for he obtains larger crops of truffles from
ground covered with young seedling oaks than from that filled with roots
of old trees. See an article on Mont Ventoux, by Charles Martins, in the
_Revue des Deux Mondes_, Avril, 1863, p. 626.
It ought to be much more generally known than it is that most, if not,
all mushrooms, even of the species reputed poisonous, may be rendered
harmless and healthful as food by soaking them for two hours in
acidulated or salt water. The water requires two or three spoonfuls of
vinegar or two spoonfuls of gray salt to the quart, and a quart of water
is enough for a pound of sliced mushrooms. After thus soaking, they are
well washed in fresh water, thrown into cold water, which is raised to
the boiling point, and, after remaining half an hour, taken out and
again washed. Gerard, to prove that "crumpets is wholesome," ate one
hundred and seventy-five pounds of the most poisonous mushrooms thus
prepared, in a single month, fed his family _ad libitum_ with the same,
and finally administered them, in heroic doses, to the members of a
committee appointed by the Council of Health of the city of Paris. See
FIGUIER, _L'Annee Scientifique_, 1862, pp. 353, 384. See _Appendix_, No.
31.
It has long been known that the Russian peasantry eat, with impunity,
mushrooms of species everywhere else regarded as very poisonous. Is it
not probable that the secret of rendering them harmless--which was known
to Pliny, though since forgotten in Italy--is possessed by the rustic
Muscovites?
[264] _Physikalische Geographie_, p. 486.
[265] _Origin of Species_, American edition, p. 69.
[266] Writers on vegetable physiology record numerous instances where
seeds have grown after lying dormant for ages. The following cases,
mentioned by Dr. Dwight (_Travels_, ii, pp. 438, 439), may be new to
many readers:
"The lands [in Panton, Vermont], which have here been once cultivated,
and again permitted to lie waste for several years, yield a rich and
fine growth of hickory [_Carya porcina_]. Of this wood there is not, I
believe, a single tree in any original forest within fifty miles from
this spot. The native growth was here white pine, of which I did not see
a single stem in a whole grove of hickory."
The hickory is a walnut, bearing a fruit too heavy to be likely to be
carried fifty miles by birds, and besides, I believe it is not eaten by
any bird indigenous to Vermont.
"A field, about five miles from Northampton, on an eminence called Rail
Hill, was cultivated about a century ago. The native growth here, and in
all the surrounding region, was wholly oak, chestnut, &c. As the field
belonged to my grandfather, I had the best opportunity of learning its
history. It contained about five acres, in the form of an irregular
parallelogram. As the savages rendered the cultivation dangerous, it was
given up. On this ground there sprang up a grove of white pines covering
the field and retaining its figure exactly. So far as I remember, there
was not in it a single oak or chestnut tree. * * * There was not a
single pine whose seeds were, or, probably, had for ages been,
sufficiently near to have been planted on this spot. The fact that these
white pines covered this field exactly, so as to preserve both its
extent and its figure, and that there were none in the neighborhood, are
decisive proofs that cultivation brought up the seeds of a former forest
within the limits of vegetation, and gave them an opportunity to
germinate."
[267] Quaint old Valvasor had observed the subduing influence of
nature's solitudes. In describing the lonely Canker-Thal, which, though
rocky, was in his time well wooded with "fir, larches, beeches, and
other trees," he says: "Gladsomeness and beauty, which dwell in many
valleys, may not be looked for there. The journey through it is
cheerless, melancholy, wearisome, and serveth to temper and mortify
over-joyousness of thought. * * * In sum it is a very wild, wherein the
wildness of human pride doth grow tame."--_Ehre der Crain_, i, p. 136,
b.
[268] Valvasor says, in the same paragraph from which I have just
quoted, "In my many journeys through this valley, I did never have sight
of so much as a single bird."
[269] Smela, in the government of Kiew, has, for some years, not
suffered at all from the locusts, which formerly came every year in vast
swarms, and the curculio, so injurious to the turnip crops, is less
destructive there than in other parts of the province. This improvement
is owing partly to the more thorough cultivation of the soil, partly to
the groves which are interspersed among the plough lands. * * * When in
the midst of the plains woods shall be planted and filled with
insectivorous birds, the locusts will cease to be a plague and a terror
to the farmer.--RENTZSCH, _Der Wald_, pp. 45, 46.
[270] England is, I believe, the only country where private enterprise
has pursued sylviculture on a really great scale, though admirable
examples have been set in many others on both sides of the Atlantic. In
England the law of primogeniture, and other institutions and national
customs which tend to keep large estates long undivided and in the same
line of inheritance, the wealth of the landholders, and the difficulty
of finding safe and profitable investments of capital, combine to afford
encouragements for the plantation of forests, which nowhere else exist
in the same degree. The climate of England, too, is very favorable to
the growth of forest trees, though the character of surface secures a
large part of the island from the evils which have resulted from the
destruction of the woods elsewhere, and therefore their restoration is a
matter of less geographical importance in England than on the Continent.
[271] The preservation of the woods on the eastern frontier of France,
as a kind of natural abattis, is also recognized by the Government of
that country as an important measure of military defence, though there
have been conflicting opinions on the subject.
[272] Let us take the supply of timber for railroad ties. According to
Clave (p. 248), France has 9,000 kilometres of railway in operation,
7,000 in construction, half of which is built with a double track.
Adding turnouts and extra tracks at stations, the number of ties
required for a single track is stated at 1,200 to the kilometre, or, as
Clave computes, for the entire network of France, 58,000,000. As the
schoolboys say, "this sum does not prove;" for 16,000 + 8,000 for the
double track halfway = 24,000, and 24,000 x 1,200 = 28,800,000.
According to Bigelow (_Les Etats Unis en 1863_, p. 439), the United
States had in operation or construction on the first of January, 1862,
51,000 miles, or about 81,000 kilometres of railroad, and the military
operations of the present civil war are rapidly extending the system.
Allowing the same proportion as in France, the American railroads
required 97,200,000 ties in 1862. The consumption of timber in Europe
and America during the present generation, occasioned by this demand,
has required the sacrifice of many hundred thousand acres of forest, and
if we add the quantity employed for telegraph posts, we have an amount
of destruction, for entirely new purposes, which is really appalling.
The consumption of wood for lucifer matches is enormous, and I have
heard of several instances where tracts of pine forest, hundreds and
even thousands of acres in extent, have been purchased and felled,
solely to supply timber for this purpose.
The demand for wood for small carvings and for children's toys is
incredibly large. Rentzsch states the export of such objects from the
town of Sonneberg alone to have amounted, in 1853, to 60,000 centner, or
three thousand tons' weight.--_Der Wald_, p. 68. See _Appendix_, No. 33.
The importance of so managing the forest that it may continue
indefinitely to furnish an adequate supply of material for naval
architecture is well illustrated by some remarks of the same author in
the valuable little work just cited. He suggests that the prosperity of
modern England is due, in no small degree, to the supplies of wood and
other material for building and equipping ships, received from the
forests of her colonies and of other countries with which she has
maintained close commercial relations, and he adds: "Spain, which by her
position seemed destined for universal power, and once, in fact,
possessed it, has lost her political rank, because during the unwise
administration of the successors of Philip II, the empty exchequer could
not furnish the means of building new fleets; for the destruction of the
forests had raised the price of timber above the resources of the
state."--_Der Wald_, p. 63.
The market price of timber, like that of all other commodities, may be
said, in a general way, to be regulated by the laws of demand and
supply, but it is also controlled by those seemingly unrelated accidents
which so often disappoint the calculations of political economists in
other branches of commerce. A curious case of this sort is noticed by
CERINI, _Dell' Impianto e Conservazione dei Boschi_, p. 17: "In the
mountains on the Lago Maggiore, in years when maize is cheap, the
woodcutters can provide themselves with corn meal enough for a week by
three days' labor, and they refuse to work the remaining four. Hence the
dealers in wood, not being able to supply the demand, for want of
laborers, are obliged to raise the price for the following season, both
for timber and for firewood; so that a low price of grain occasions a
high price of building lumber and of fuel. The consequence is, that
though the poor have supplied themselves cheaply with food, they must
pay dear for firewood, and they cannot get work, because the high price
of lumber has discouraged repairs and building, the expense of which
landed proprietors cannot undertake when their incomes have been reduced
by sales of grain at low rates, and hence there is not demand enough for
lumber to induce the timber merchants to furnish employment to the
woodmen."
[273] Besides the substitution of iron for wood, a great saving of
consumption of this latter material has been effected by the revival of
ancient methods of increasing its durability, and the invention of new
processes for the same purpose. The most effectual preservative yet
discovered for wood employed on land, is sulphate of copper, a solution
of which is introduced into the pores of the wood while green, by
soaking, by forcing-pumps, or, most economically, by the simple pressure
of a column of the fluid in a small pipe connected with the end of the
piece of timber subjected to the treatment. Clave (_Etudes Forestieres_,
pp. 240-249) gives an interesting account of the various processes
employed for rendering wood imperishable, and states that railroad ties
injected with sulphate of copper in 1846, were found absolutely
unaltered in 1855; and telegraphic posts prepared two years earlier, are
now in a state of perfect preservation.
For many purposes, the method of injection is too expensive, and some
simpler process is much to be desired. The question of the proper time
of felling timber is not settled, and the best modes of air, water, and
steam seasoning are not yet fully ascertained. Experiments on these
subjects would be well worth the patronage of governments in new
countries, where they can be very easily made, without the necessity of
much waste of valuable material, and without expensive arrangements for
observation.
The practice of stripping living trees of their bark some years before
they are felled, is as old as the time of Vitruvius, but is much less
followed than it deserves, partly because the timber of trees so treated
inclines to crack and split, and partly because it becomes so hard as to
be wrought with considerable difficulty.
In America, economy in the consumption of fuel has been much promoted by
the substitution of coal for wood, the general use of stoves both for
wood and coal, and recently by the employment of anthracite in the
furnaces of stationary and locomotive steam-engines. All the objections
to the use of anthracite for this latter purpose appear to have been
overcome, and the improvements in its combustion have been attended with
a great pecuniary saving, and with much advantage to the preservation of
the woods.
The employment of coal has produced a great reduction in the consumption
of fire wood in Paris. In 1815, the supply of fire wood for the city
required 1,200,000 steres, or cubic metres; in 1859, it had fallen to
501,805, while, in the mean time, the consumption of coal had risen from
600,000 to 432,000,000 metrical quintals. See CLAVE, _Etudes_, p. 212.
I think there must be some error in this last sum, as 432 millions of
metrical quintals would amount to 43 millions of tons, a quantity which
it is difficult to suppose could be consumed in the city of Paris. The
price of fire wood has scarcely advanced at all in Paris for half a
century, though that of timber generally has risen enormously.
[274] In the first two years of the present civil war in the United
States, twenty-eight thousand walnut trees were felled to supply a
single European manufactory of gunstocks for the American market.
[275] Among the indirect proofs of the comparatively recent existence of
extensive forests in France, may be mentioned the fact, that wolves were
abundant, not very long since, in parts of the empire where there are
now neither wolves nor woods to shelter them. Arthur Young more than
once speaks of the "innumerable multitudes" of these animals which
infested France in 1789, and George Sand states, in the _Histoire de ma
Vie_, that some years after the restoration of the Bourbons, they chased
travellers on horseback in the Southern provinces, and literally knocked
at the doors of her father-in-law's country seat.
[276] In the _Recepte Veritable_, Palissy having expressed his
indignation at the folly of men in destroying the woods, his
interlocutor defends the policy of felling them, by citing the example
of "divers bishops, cardinals, priors, abbots, monkeries, and chapters,
which, by cutting their woods, have made three profits," the sale of the
timber, the rent of the ground, and the "good portion" they received of
the grain grown by the peasants upon it. To this argument, Palissy
replies: "I cannot enough detest this thing, and I call it not an error,
but a curse and a calamity to all France; for when forests shall be cut,
all arts shall cease, and they which practise them shall be driven out
to eat grass with Nebuchadnezzar and the beasts of the field. I have
divers times thought to set down in writing the arts which shall perish
when there shall be no more wood; but when I had written down a great
number, I did perceive that there could be no end of my writing, and
having diligently considered, I found there was not any which could be
followed without wood." * * "And truly I could well allege to thee a
thousand reasons, but 'tis so cheap a philosophy, that the very chamber
wenches, if they do but think, may see that without wood, it is not
possible to exercise any manner of human art or cunning."--_[OE]uvres
de_ BERNARD PALISSY, p. 89.
[277] Since writing the above paragraph, I have found the view I have
taken of this point confirmed by the careful investigations of Rentzsch,
who estimates the proper proportion of woodland to entire surface at
twenty-three per cent. for the interior of Germany, and supposes that
near the coast, where the air is supplied with humidity by evaporation
from the sea, it might safely be reduced to twenty per cent. See
Rentzsch's very valuable prize essay, _Der Wald im Haushalt der Natur
und der Volkswirthschaft_, cap. viii.
The due proportion in France would considerably exceed that for the
German States, because France has relatively more surface unfit for any
growth but that of wood, because the form and geological character of
her mountains expose her territory to much greater injury from torrents,
and because at least her southern provinces are more frequently visited
both by extreme drought and by deluging rains.
[278] _Etudes sur l'Economie Forestiere_, p. 261. Clave adds (p. 262):
"The Russian forests are very unequally distributed through the
territory of this vast empire. In the north they form immense masses,
and cover whole provinces, while in the south they are so completely
wanting that the inhabitants have no other fuel than straw, dung,
rushes, and heath." * * * "At Moscow, firewood costs thirty per cent.
more than at Paris, while, at the distance of a few leagues, it sells
for a tenth of that price."
This state of things is partly due to the want of facilities of
transportation, and some parts of the United States are in a similar
condition. During a severe winter, six or seven years ago, the sudden
freezing of the canals and rivers, before a large American town had
received its usual supply of fuel, occasioned an enormous rise in the
price of wood and coal, and the poor suffered severely for want of it.
Within a few hours of the city were large forests and an abundant stock
of firewood felled and prepared for burning. This might easily have been
carried to town by the railroads which passed through the woods; but the
managers of the roads refused to receive it as freight, because the
opening of a new market for wood might raise the price of the fuel they
employed for their locomotives.
Hohenstein, who was long professionally employed as a forester in
Russia, describes the consequences of the general war upon the woods in
that country as already most disastrous, and as threatening still more
ruinous evils. The river Volga, the life artery of Russian internal
commerce, is drying up from this cause, and the great Muscovite plains
are fast advancing to a desolation like that of Persia.--_Der Wald_, p.
223.
The level of the Caspian Sea is eighty-three feet lower than that of the
Sea of Azoff, and the surface of Lake Aral is fast sinking. Von Baer
maintains that the depression of the Caspian was produced by a sudden
subsidence, from geological causes, and not gradually by excess of
evaporation over supply. See _Kaspische Studien_, p. 25. But this
subsidence diminished the area and consequently the evaporation of that
sea, and the rivers which once maintained its ancient equilibrium ought
to raise it to its former level, if their own flow had not been
diminished. It is, indeed, not proved that the laying bare of a wooded
country diminishes the total annual precipitation upon it; but it is
certain that the summer evaporation from the surface of a champaign
region, like that through which the Volga, its tributaries, and the
feeders of Lake Aral flow, is increased by the removal of its woods.
Hence, though as much rain may still fall in the valleys of those rivers
as when their whole surface was covered with forests, a less quantity of
water may be delivered by them since their basins were cleared, and
therefore the present condition of the inland waters in question may be
due to the removal of the forests in their basins.
[279] Rentzsch _(Der Wald, etc._, pp. 123, 124) states the proportions
of woodland in different European countries as follows:
---------------+----------+-----------
| |Acres per
| Per cent.| head of
| |population.
---------------+----------+-----------
Germany | 26.58 | 0.6638
Great Britain | 5. | 0.1
France | 16.79 | 0.3766
Russia | 30.90 | 4.28
Sweden | 60. | 8.55
Norway | 66. | 24.61
Denmark | 5.50 | 0.22
Switzerland | 15. | 0.396
Holland | 7.10 | 0.12
Belgium | 18.52 | 0.186
Spain | 5.52 | 0.291
Portugal | 4.40 | 0.182
Sardinia | 12.29 | 0.223
Naples | 9.43 | 0.138
---------------+----------+-----------
Probably no European countries can so well dispense with the forests, in
their capacity of conservative influences, as England and Ireland. Their
insular position and latitude secure an abundance of atmospheric
moisture, and the general inclination of surface is not such as to
expose it to special injury from torrents. The due proportion of
woodland in England and Ireland is, therefore, almost purely an
economical question, to be decided by the comparative direct pecuniary
return from forest growth, pasturage, and plough land.
In Scotland, where the country is for the most part more broken and
mountainous, the general destruction of the forests has been attended
with very serious evils, and it is in Scotland that many of the most
extensive British forest plantations have now been formed. But although
the inclination of surface in Scotland is rapid, the geological
constitution of the soil is not of a character to promote such
destructive degradation by running water as in Southern France, and it
has not to contend with the parching droughts by which the devastations
of the torrents are rendered more injurious in that part of the French
empire.
In giving the proportion of woodland to population, I compute Rentzsch's
Morgen at .3882 of an English acre, because I find, by Alexander's most
accurate and valuable Dictionary of Weights and Measures, that this is
the value of the Dresden Morgen, and Rentzsch is a Saxon writer. In the
different German States, there are more than twenty different land
measures known by the name of Morgen, varying from about one third of an
acre to more than three acres in value. When will the world be wise
enough to unite in adopting the French metrical and monetary systems? As
to the latter, never while Christendom continues to be ruled by money
changers, who can compel you to part with your sovereigns in France at
twenty-five francs, and in England to accept fifteen shillings for your
napoleons. I speak as a sufferer. _Experto crede Roberto._
[280] According to the maxims of English jurisprudence, the common law
consists of general customs so long established that "the memory of man
runneth not to the contrary." In other words, long custom makes law. In
new countries, the change of circumstances creates new customs, and, in
time, new law, without the aid of legislation. Had the American
colonists observed a more sparing economy in the treatment of their
woods, a new code of customary forest law would have sprung up and
acquired the force of a statute. Popular habit was fast elaborating the
fundamental principles of such a code, when the rapid increase in the
value of timber, in consequence of the reckless devastation of the
woodlands, made it the interest of the proprietors to interfere with
this incipient system of forest jurisprudence, and appeal to the rules
of English law for the protection of their woods. The courts have
sustained these appeals, and forest property is now legally as
inviolable as any other, though common opinion still combats the course
of judicial decision on such questions.
In the United States, swarms of honey bees, on leaving the parent hive,
often take up their quarters in hollow trees in the neighboring woods.
By the early customs of New England, the finder of a "bee tree" on the
land of another owner was regarded as entitled to the honey by right of
discovery; and as a necessary incident of that right, he might cut the
tree, at the proper season, without asking permission of the proprietor
of the soil. The quantity of "wild honey" in a tree was often large, and
"bee hunting" was so profitable that it became almost a regular
profession. The "bee hunter" sallied forth with a small box containing
honey and a little vermilion. The bees which were attracted by the honey
marked themselves with the vermilion, and hence were more readily
followed in their homeward flight, and recognized when they returned a
second time for booty. When loaded with spoil, this insect returns to
his hive by the shortest route, and hence a straight line is popularly
called in America a "bee line." By such a line, the hunter followed the
bees to their sylvan hive, marked the tree with his initials, and
returned to secure his prize in the autumn. When the right of the "bee
hunter" was at last disputed by the land proprietors, it was with
difficulty that judgments could be obtained, in inferior courts, in
favor of the latter, and it was only after repeated decisions of the
higher legal tribunals that the superior right of the owner of the soil
was at last acquiesced in.
[281] _Etude sur le Reboisement des Montagnes_, p. 5.
[282] "In America," says Clave (p. 124, 125), "where there is a vast
extent of land almost without pecuniary value, but where labor is dear
and the rate of interest high, it is profitable to till a large surface
at the least possible cost; _extensive_ cultivation is there the most
advantageous. In England, France, and Germany, where every corner of
soil is occupied, and the least bit of ground is sold at a high price,
but where labor and capital are comparatively cheap, it is wisest to
employ _intensive_ cultivation. * * * All the efforts of the cultivator
ought to be directed to the obtaining of a given result with the least
sacrifice, and there is equally a loss to the commonwealth if the
application of improved agricultural processes be neglected where
they are advantageous, or if they be employed where they are not
required. * * * In this point of view, sylviculture must follow the same
laws as agriculture, and, like it, be modified according to the
economical conditions of different states. In countries abounding in
good forests, and thinly peopled, elementary and cheap methods must be
pursued; in civilized regions, where a dense population requires that
the soil shall be made to produce all it can yield, the regular
artificial forest, with all the processes that science teaches, should
be cultivated. It would be absurd to apply to the endless woods of
Brazil and of Canada the method of the Spessart by "double stages," and
not less so in our country, where every yard of ground has a high value,
to leave to nature the task of propagating trees, and to content
ourselves with cutting, every twenty or twenty-five years, the meagre
growths that chance may have produced."
[283] It is often laid down as a universal law, that the wood of trees
of slow vegetation is superior to that of quick growth. This is one of
those commonplaces by which men love to shield themselves from the labor
of painstaking observation. It has, in fact, so many exceptions, that it
may be doubted whether it is in any sense true. Most of the cedars are
slow of growth; but while the timber of some of them is firm and
durable, that of others is light, brittle, and perishable. The hemlock
spruce is slower of growth than the pines, but its wood is of very
little value. The pasture oak and beech show a breadth of grain--and, of
course, an annual increment--twice as great as trees of the same species
grown in the woods; and the American locust, _Robinia pseudacacia_, the
wood of which is of extreme toughness and durability, is, of all trees
indigenous to Northeastern America, by far the most rapid in growth.
As an illustration of the mutual interdependence of the mechanic arts, I
may mention that in Italy, where stone, brick, and plaster are almost
the only materials used in architecture, and where the "hollow ware"
kitchen implements are of copper or of clay, the ordinary tools for
working wood are of a very inferior description, and the locust timber
is found too hard for their temper. Southey informs us, in "Espriella's
Letters," that when a small quantity of mahogany was brought to England,
early in the last century, the cabinetmakers were unable to use it, from
the defective temper of their tools, until the demand for furniture from
the new wood compelled them to improve the quality of their implements.
In America, the cheapness of wood long made it the preferable material
for almost all purposes to which it could by any possibility be applied.
The mechanical cutlery and artisans' tools of the United States are of
admirable temper, finish, and convenience, and no wood is too hard, or
otherwise too refractory, to be wrought with great facility, both by
hand tools and by the multitude of ingenious machines which the
Americans have invented for this purpose.
[284] _Etudes Forestieres_, p. 7.
[285] _Etudes Forestieres_, p. 7.
[286] For very full catalogues of American forest trees, and remarks on
their geographical distribution, consult papers on the subject by Dr. J.
G. Cooper, in the Report of the Smithsonian Institution for 1858, and
the Report of the United States Patent Office, Agricultural Division,
for 1860.
[287] Although Spenser's catalogue of trees occurs in the first canto of
the first book of the "Faery Queene"--the only canto of that exquisite
poem actually read by most students of English literature--it is not so
generally familiar as to make the quotation of it altogether
superfluous:
VII.
Enforst to seeke some covert nigh at hand,
A shadie grove not farr away they spide,
That promist ayde the tempest to withstand;
Whose loftie trees, yelad with sommers pride,
Did spred so broad, that heavens light did hide,
Not perceable with power of any starr:
And all within were pathes and alleies wide,
With footing worne, and leading inward farr;
Faire harbour that them seems; so in they entred ar.
VIII.
And foorth they passe, with pleasure forward led,
Joying to heare the birdes sweete harmony,
Which therein shrouded from the tempest dred,
Seemd in their song to scorne the cruell sky.
Much can they praise the trees so straight and hy,
The sayling pine; the cedar stout and tall;
The vine-propp elm; the poplar never dry;
The builder oake, sole king of forrests all;
The aspine good for staves; the cypresse funerall;
IX.
The laurell, meed of mightie conquerours
And poets sage; the firre that weepeth still;
The willow, worne of forlorn paramours;
The eugh, obedient to the benders will;
The birch for shaftes; the sallow for the mill;
The mirrhe sweete-bleeding in the bitter wound;
The warlike beech; the ash for nothing ill;
The fruitfull olive; and the platane round;
The carver holme; the maple seeldom inward sound.
[288] The walnut is a more valuable tree than is generally supposed. It
yields one third of the oil produced in France, and in this respect
occupies an intermediate position between the olive of the south, and
the oleaginous seeds of the north. A hectare (about two and a half
acres), will produce nuts to the value of five hundred francs a year,
which cost nothing but the gathering. Unfortunately, its maturity must
be long waited for, and more nut-trees are felled than planted. The
demand for its wood in cabinet work is the principal cause of its
destruction. See LAVERGNE, _Economie Rurale de la France_, p. 253.
According to Cosimo Ridolfi (Lezioni Orali, ii. p. 424), France obtains
three times as much oil from the walnut as from the olive, and nearly as
much as from all oleaginous seeds together. He states that the walnut
bears nuts at the age of twenty years, and yields its maximum product at
seventy, and that a hectare of ground, with thirty trees, or twelve to
the acre, is equal to a capital of twenty-five hundred francs.
The nut of this tree is known in the United States as the "English
walnut." The fruit and the wood much resemble those of the American
black walnut, _Juglans nigra_, but for cabinet work the American is the
more beautiful material, especially when the large knots are employed.
The timber of the European species, when straight grained, and _clear_,
or free from knots, is, for ordinary purposes, better than that of the
American black walnut, but bears no comparison with the wood of the
hickory, when strength combined with elasticity is required, and its nut
is very inferior in taste to that of the shagbark, as well as to the
butternut, which it somewhat resembles.
"The chestnut is more valuable still, for it produces on a sterile soil,
which, without it, would yield only ferns and heaths, an abundant
nutriment for man."--LAVERGNE, _Economie Rurale de la France_, p. 253.
I believe the varieties developed by cultivation are less numerous in
the walnut than in the chestnut, which latter tree is often grafted in
Southern Europe.
[289] This fir is remarkable for its tendency to cicatrize or heal over
its stumps, a property which it possesses in common with some other
firs, the maritime pine, and the European larch. When these trees grow
in thick clumps, their roots are apt to unite by a species of natural
grafting, and if one of them be felled, although its own proper rootlets
die, the stump may continue, sometimes for a century, to receive
nourishment from the radicles of the surrounding trees, and a dome of
wood and bark of considerable thickness be formed over it. The
cicatrization is, however, only apparent, for the entire stump, except
the outside ring of annual growth, soon dies, and even decays within its
covering, without sending out new shoots.
[290] At the age of twelve or fifteen years, the cork tree is stripped
of its outer bark for the first time. This first yield is of inferior
quality, and is employed for floats for nets and buoys, or burnt for
lampblack. After this, a new layer of cork, an inch or an inch and a
quarter in thickness, is formed about once in ten years, and is removed
in large sheets without injury to the tree, which lives a hundred and
fifty years or more. According to Clave (p. 252), the annual product of
a forest of cork oaks is calculated at about 660 kilogrammes, worth 150
francs, to the hectare, which, deducting expenses, leaves a profit of
100 francs. This is about equal to 250 pound weight, and eight dollars
profit to the acre. The cork oaks of the national domain in Algeria
cover about 500,000 acres, and are let to individuals at rates which are
expected, when the whole is rented, to yield to the state a revenue of
about $2,000,000.
George Sand, in the _Histoire de ma Vie_, speaks of the cork forests in
Southern France as among the most profitable of rural possessions, and
states, what I do not remember to have seen noticed elsewhere, that
Russia is the best customer for cork. The large sheets taken from the
trees are slit into thin plates, and used to line the walls of
apartments in that cold climate.
[291] The walnut, the chestnut, the apple, and the pear are common to
the border between the countries I have mentioned, but the range of the
other trees is bounded by the Alps, and by a well-defined and sharply
drawn line to the west of those mountains. I cannot give statistical
details as to the number of any of the trees in question, or as to the
area they would cover if brought together in a given country. From some
peculiarity in the sky of Europe, cultivated plants will thrive, in
Northern Italy, in Southern France, and even in Switzerland, under a
depth of shade where no crop, not even grass, worth harvesting, would
grow in the United States with an equally high summer temperature. Hence
the cultivation of all these trees is practicable in Europe to a greater
extent than would be supposed reconcilable with the interests of
agriculture. Some idea of the importance of the olive orchards may be
formed from the fact that Sicily alone, an island scarcely exceeding
10,000 square miles in area, of which one third at least is absolutely
barren, has exported to the single port of Marseilles more than
2,000,000 pounds weight of olive oil per year, for the last twenty
years.
[292] It is hard to say how far the peculiar form of the graceful crown
of this pine is due to pruning. It is true that the extremities of the
topmost branches are rarely lopped, but the lateral boughs are almost
uniformly removed to a very considerable height, and it is not
improbable that the shape of the top is thereby affected.
[293] Besides this, in a country so diversified in surface--I wish we
could with the French say _accidented_--as Italy with the exception of
the champaign region drained by the Po, every new field of view requires
either an extraordinary _coup d'[oe]il_ in the spectator, or a long
study, in order to master its relief, its plans, its salient and
retreating angles. In summer, the universal greenery confounds light and
shade, distance and foreground; and though the impression upon a
traveller, who journeys for the sake of "sensations," may be
strengthened by the mysterious annihilation of all standards for the
measurement of space, yet the superior intelligibility of the winter
scenery of Italy is more profitable to those who see with a view to
analyze.
[294] Copse, or coppice, from the French _couper_, to cut, signifies
properly a wood the trees of which are cut at certain periods of
immature growth, and allowed to shoot up again from the roots; but it
has come to signify, very commonly, a young wood, grove, or thicket,
without reference to its origin, or to its character of a forest crop.
[295] It has been recently stated, upon the evidence of the Government
foresters of Greece, and of the queen's gardener, that a large wood has
been discovered in Arcadia, consisting of a fir which has the property
of sending up both vertical and lateral shoots from the stump of felled
trees and forming a new crown. It was at first supposed that this forest
grew only on the "mountains," of which the hero of About's most amusing
story, _Le Roi des Montagnes_, was "king;" but it is now said that small
stumps, with the shoots attached, have been sent to Germany, and
recognized by able botanists as true natural products.
[296] Natural forests are rarely, if ever, composed of trees of a single
species, and experience has shown that oaks and other broad-leaved
trees, planted as artificial woods, require to be mixed, or associated
with others of different habits.
In the forest of Fontainebleau, "oaks, mingled with beeches in due
proportion," says Clave, "may arrive at the age of five or six hundred
years in full vigor, and attain dimensions which I have never seen
surpassed; when, however, they are wholly unmixed with other trees, they
begin to decay and die at the top, at the age of forty or fifty years,
like men, old before their time, weary of the world, and longing only to
quit it. This has been observed in most of the oak plantations of which
I have spoken, and they have not been able to attain to full growth.
When the vegetation was perceived to languish, they were cut, in the
hope that this operation would restore their vigor, and that the new
shoots would succeed better than the original trees; and, in fact, they
seemed to be recovering for the first few years. But the shoots were
soon attacked by the same decay, and the operation had to be renewed at
shorter and shorter intervals, until at last it was found necessary to
treat as coppices plantations originally designed for the full-growth
system. Nor was this all: the soil, periodically bared by these
cuttings, became impoverished, and less and less suited to the growth of
the oak. * * * It was then proposed to introduce the pine and plant with
it the vacancies and glades. * * * By this means, the forest was saved
from the ruin which threatened it, and now more than 10,000 acres of
pines, from fifteen to thirty years old, are disseminated at various
points, sometimes intermixed with broad-leaved trees, sometimes forming
groves by themselves."--_Revue des Deux Mondes_, Mai, 1863, pp. 153,
154.
The forests of Denmark, which, in modern times, have been succeeded by
the beech--a species more inclined to be exclusive than any other
broad-leaved tree--were composed of birches, oaks, firs, aspens,
willows, hazel, and maple, the first three being the leading species. At
present, the beech greatly predominates.--VAUPELL, _Boegens Indvandring_,
pp. 19, 20.
[297] _Etudes Forestieres_, p. 89.
[298] The grounds which it is most important to clothe with wood as a
conservative influence, and which, also, can best be spared from
agricultural use, are steep hillsides. But the performance of all the
offices of the forester to the tree--seeding, planting, thinning, and
finally felling and removing for consumption--is more laborious upon a
rapid declivity than on a level soil, and at the same time it is
difficult to apply irrigation or manures to trees so situated.
Experience has shown that there is great advantage in terracing the face
of a hill before planting it, both as preventing the wash of the earth
by checking the flow of water down its slope, and as presenting a
surface favorable for irrigation, as well as for manuring and
cultivating the tree. But even without so expensive a process, very
important results have been obtained by simply ditching declivities. "In
order to hasten the growth of wood on the flanks of a mountain, Mr.
Eugene Chevandier divided the slope into zones forty or fifty feet wide,
by horizontal ditches closed at both ends, and thereby obtained, from
firs of different ages, shoots double the dimensions of those which grew
on a dry soil of the same character, where the water was allowed to run
off without obstruction."--DUMONT, _Des Travaux Publics, etc._, pp.
94-96.
The ditches were about two feet and a half deep, and three feet and a
half wide, and they cost about forty francs the hectare, or three
dollars the acre. This extraordinary growth was produced wholly by the
retention of the rain water in the ditches, whence it filtered through
the whole soil and supplied moisture to the roots of the trees. It may
be doubted whether in a climate cold enough to freeze the entire
contents of the ditches in winter, it would not be expedient to draw off
the water in the autumn, as the presence of so large a quantity of ice
in the soil might prove injurious to trees too young and small to
shelter the ground effectually against frost.
Chevandier computes that, if the annual growth of the pine in the marshy
soil of the Vosges be represented by one, it will equal two in dry
ground, four or five on slopes so ditched or graded as to retain the
water flowing upon them from roads or steep declivities, and six where
the earth is kept constantly moist by infiltration from running
brooks.--_Comptes Rendus a l'Academie des Sciences_--t. xix, Juillet,
Dec., 1844, p. 167.
The effect of accidental irrigation is well shown in the growth of the
trees planted along the canals of irrigation which traverse the fields
in many parts of Italy. They flourish most luxuriantly, in spite of
continual lopping, and yield a very important contribution to the stock
of fuel for domestic use; while trees, situated so far from canals as to
be out of the reach of infiltration from them, are of much slower
growth, under circumstances otherwise equally favorable.
In other experiments of Chevandier, under better conditions, the yield
of wood was increased, by judicious irrigation, in the ratio of seven to
one, the profits in that of twelve to one. At the Exposition of 1855,
Chambrelent exhibited young trees, which, in four years from the seed,
had grown to the height of sixteen and twenty feet, and the diameter of
ten and twelve inches. Chevandier experimented with various manures, and
found that some of them might be profitably applied to young, but not to
old trees, the quantity required in the latter case being too great.
Wood ashes and the refuse of soda factories are particularly
recommended. I have seen an extraordinary growth produced in fir trees
by the application of soapsuds.
[299] Although the economy of the forest has received little attention
in the United States, no lover of American nature can have failed to
observe a marked difference between a native wood from which cattle are
excluded and one where they are permitted to browse. A few seasons
suffice for the total extirpation of the "underbrush," including the
young trees on which alone the reproduction of the forest depends, and
all the branches of those of larger growth which hang within reach of
the cattle are stripped of their buds and leaves, and soon wither and
fall off. These effects are observable at a great distance, and a wood
pasture is recognized, almost as far as it can be seen, by the
regularity with which its lower foliage terminates at what Ruskin
somewhere calls the "cattle line." This always runs parallel to the
surface of the ground, and is determined by the height to which domestic
quadrupeds can reach to feed upon the leaves. In describing a visit to
the grand-ducal farm of San Rossore near Pisa, where a large herd of
camels is kept, Chateauvieux says: "In passing through a wood of
evergreen oaks, I observed that all the twigs and foliage of the trees
were clipped up to the height of about twelve feet above the ground,
without leaving a single spray below that level. I was informed that the
browsing of the camels had trimmed the trees as high as they could
reach."--LULLIN DE CHATEAUVIEUX, _Lettres sur l'Italie_, p. 113.
The removal of the shelter afforded by the brushwood and the pendulous
branches of trees permits drying and chilling winds to parch and cool
the ground, and of course injuriously affects the growth of the wood.
But this is not all. The tread of quadrupeds exposes and bruises the
roots of the trees, which often die from this cause, as any one may
observe by following the paths made by cattle through woodlands.
[300] I have remarked elsewhere that most insects which deposit and
hatch their eggs in the wood of the natural forest confine themselves to
dead trees. Not only is this the fact, but it is also true that many of
the borers attack only freshly cut timber. Their season of labor is a
short one, and unless the tree is cut during this period, it is safe
from them. In summer you may hear them plying their augers in the wood
of a young pine with soft green bark, as you sit upon its trunk, within
a week after it has been felled, but the windfalls of the winter lie
uninjured by the worm and even undecayed for centuries. In the pine
woods of New England, after the regular lumberman has removed the
standing trees, these old trunks are hauled out from the mosses and
leaves which half cover them, and often furnish excellent timber. The
slow decay of such timber in the woods, it may be remarked, furnishes
another proof of the uniformity of temperature and humidity in the
forest, for the trunk of a tree lying on grass or plough land, and of
course exposed to all the alternations of climate, hardly resists
complete decomposition for a generation. The forests of Europe exhibit
similar facts. Wessely, in a description of the primitive wood of
Neuwald in Lower Austria, says that the windfalls required from 150 to
200 years for entire decay.-_-Die Oesterreichischen Alpenlaender und ihre
Forste_, p. 312.
[301] VAUPELL, _Boegens Indvandring i de Danske Skove_, pp. 29, 46.
Vaupell further observes, on the page last quoted: "The removal of
leaves is injurious to the forest, not only because it retards the
growth of trees, but still more because it disqualifies the soil for the
production of particular species. When the beech languishes, and the
development of its branches is less vigorous and its crown less
spreading, it becomes unable to resist the encroachments of the fir.
This latter tree thrives in an inferior soil, and being no longer
stifled by the thick foliage of the beech, it spreads gradually through
the wood, while the beech retreats before it and finally perishes."
The study of the natural order of succession in forest trees is of the
utmost importance in sylviculture, because it guides us in the selection
of the species to be employed in planting a new or restoring a decayed
forest. When ground is laid bare both of trees and of vegetable mould,
and left to the action of unaided and unobstructed nature, she first
propagates trees which germinate and grow only under the influence of a
full supply of light and air, and then, in succession, other species,
according to their ability to bear the shade and their demand for more
abundant nutriment. In Northern Europe, the larch, the white birch, the
aspen, first appear; then follow the maple, the alder, the ash, the fir;
then the oak and the linden; and then the beech. The trees called by
these respective names in the United States are not specifically the
same as their European namesakes, nor are they always even the
equivalents of these latter, and therefore the order of succession in
America would not be precisely as indicated by the foregoing list, but
it nevertheless very nearly corresponds to it.
It is thought important to encourage the growth of the beech in Denmark
and Northern Germany, because it upon the whole yields better returns
than other trees, and particularly because it appears not to exhaust,
but on the contrary to enrich the soil; for by shedding its leaves it
returns to it most of the nutriment it has drawn from it, and at the
same time furnishes a solvent which aids materially in the decomposition
of its mineral constituents.
When the forest is left to itself, the order of succession is constant,
and its occasional inversion is always explicable by some human
interference. It is curious that the trees which require most light are
content with the poorest soils, and _vice versa_. The trees which first
appear are also those which propagate themselves farthest to the north.
The birch, the larch, and the fir bear a severer climate than the oak,
the oak than the beech. "These parallelisms," says Vaupell, "are very
interesting, because they are entirely independent of each other," and
each prescribes the same order of succession.--_Boegens Indvandring_, p.
42.
[302] When vigorous young locusts, of two or three inches in diameter,
are polled, they throw out a great number of very thick-leaved shoots,
which arrange themselves in a globular head, so unlike the natural crown
of the acacia, that persons familiar only with the untrained tree often
take them for a different species.
[303] The two ideas expressed in the text are not exactly equivalent,
because, though the consumption of animal food diminishes the amount of
vegetable aliment required for human use, yet the animals themselves
consume a great quantity of grain and roots grown on ground ploughed and
cultivated as regularly and as laboriously as any other.
The 170,000,000 bushels of oats raised in the United States in 1860, and
fed to the 6,000,000 horses, the potatoes, the turnips, and the maize
employed in fattening the oxen, the sheep, and the swine slaughtered the
same year, occupied an extent of ground which, cultivated by hand labor
and with Chinese industry and skill, would probably have produced a
quantity of vegetable food equal in alimentary power to the flesh of the
quadrupeds killed for domestic use. Hence, so far as the naked question
of _amount_ of aliment is concerned, the meadows and the pastures might
as well have remained in the forest condition.
[304] According to Clave (_Etudes_, p. 159), the net revenue from the
forests of the state in France, making no allowance for interest on the
capital represented by the forest, is two dollars per acre. In Saxony it
is about the same, though the cost of administration is twice as much as
in France; in Wuertemberg it is about a dollar an acre; and in Prussia,
where half the income is consumed in the expenses of administration, it
sinks to less than half a dollar. This low rate in Prussia is partly
explained by the fact that a considerable proportion of the annual
product of wood is either conceded to persons claiming prescriptive
rights, or sold, at a very small price, to the poor. Taking into account
the capital invested in forest land, and adding interest upon it,
Pressler calculates that a pine wood, managed with a view to felling it
when eighty years old, would yield only one eighth of one per cent.
annual profit; a fir wood, at one hundred years, one sixth of one per
cent.; a beech wood, at one hundred and twenty years, one fourth of one
per cent. The same author (p. 335) gives the net income of the New
forest in England, over and above expenses, interest not computed, at
twenty-five cents per acre only. In America, where no expense is
bestowed upon the woods, the annual growth would generally be estimated
much higher.
[305] It is rare that a middle-aged American dies in the house where he
was born, or an old man even in that which he has built; and this is
scarcely less true of the rural districts, where every man owns his
habitation, than of the city, where the majority live in hired houses.
This life of incessant flitting is unfavorable for the execution of
permanent improvements of every sort, and especially of those which,
like the forest, are slow in repaying any part of the capital expended
in them. It requires a very generous spirit in a landholder to plant a
wood on a farm he expects to sell, or which he knows will pass out of
the hands of his descendants at his death. But the very fact of having
begun a plantation would attach the proprietor more strongly to the soil
for which he had made such a sacrifice; and the paternal acres would
have a greater value in the eyes of a succeeding generation, if thus
improved and beautified by the labors of those from whom they were
inherited. Landed property, therefore, the transfer of which is happily
free from every legal impediment or restriction in the United States,
would find, in the feelings thus prompted, a moral check against a too
frequent change of owners, and would tend to remain long enough in one
proprietor or one family to admit of gradual improvements which would
increase its value both to the possessor and to the state.
[306] It has been often asserted by eminent writers that a part of the
fens in Lincolnshire was reclaimed by sea dikes under the government of
the Romans. I have found no ancient authority in support of this
allegation, nor can I refer to any passage in Roman literature in which
sea dikes are expressly mentioned otherwise than as walls or piers,
except that in Pliny (_Hist. Nat._ xxxvi, 24), where it is said that the
Tyrrhenian sea was excluded from the Lucrine lake by dikes.
[307] A friend has recently suggested to me an interesting illustration
of the applicability of military instrumentalities to pacific art. The
sale of gunpowder in the United States, he informs me, is smaller since
the commencement of the present rebellion than before, because the war
has caused the suspension of many public and private improvements, in
the execution of which great quantities of powder were used for
blasting.
It is alleged that the same observation was made in France during the
Crimean war, and that, in general, not ten per cent. of the powder
manufactured on either side of the Atlantic is employed for military
purposes.
It is a fact not creditable to the moral sense of modern civilization,
that very many of the most important improvements in machinery and the
working of metals have originated in the necessities of war, and that
man's highest ingenuity has been shown, and many of his most remarkable
triumphs over natural forces achieved, in the contrivance of engines for
the destruction of his fellow man. The military material employed by the
first Napoleon has become, in less than two generations, nearly as
obsolete as the sling and stone of the shepherd, and attack and defence
now begin at distances to which, half a century ago, military
reconnoissances hardly extended. Upon a partial view of the subject, the
human race seems destined to become its own executioner--on the one
hand, exhausting the capacity of the earth to furnish sustenance to her
taskmaster; on the other, compensating diminished production by
inventing more efficient methods of exterminating the consumer.
But war develops great civil virtues, and brings into action a degree
and kind of physical energy which seldom fails to awaken a new
intellectual life in a people that achieves great moral and political
results through great heroism and endurance and perseverance. Domestic
corruption has destroyed more nations than foreign invasion, and a
people is rarely conquered till it has deserved subjugation.
[308] STARING, _Voormaals en Thans_, p. 150.
[309] Idem, p. 163. Much the largest proportion of the lands so
reclaimed, though for the most part lying above low-water tidemark, are
at a lower level than the Lincolnshire fens, and more subject to
inundation from the irruptions of the sea.
[310] _Die Inseln und Marschen der Herzogthuemer Schleswig und Holstein_,
iii, p. 151.
[311] The purely agricultural island of Pelworm, off the coast of
Schleswig, containing about 10,000 acres, annually expends for the
maintenance of its dikes not less than L6,000 sterling, or nearly
$30,000.--J. G. KOHL, _Inseln und Marschen Schleswig's und Holstein's_,
ii, p. 394.
The original cost of the dikes of Pelworm is not stated.
"The greatest part of the province of Zeeland is protected by dikes
measuring 250 miles in length, the maintenance of which costs, in
ordinary years, more than a million guilders [above $400,000]. * * * The
annual expenditure for dikes and hydraulic works in Holland is from five
to seven million guilders" [$2,000,000 to $2,800,000].--WILD, _Die
Niederlande_, i, p. 62.
One is not sorry to learn that the Spanish tyranny in the Netherlands
had some compensations. The great chain of ring dikes which surrounds a
large part of Zeeland is due to the energy of Caspar de Robles, the
Spanish governor of that province, who in 1570 ordered the construction
of these works at the public expense, as a substitute for the private
embankments which had previously partially served the same
purpose.--WILD, _Die Niederlande_, i, p. 62.
[312] STARING, _Voormaals en Thans_, p. 163.
[313] _Voormaals en Thans_, pp. 150, 151.
[314] STARING, _Voormaals en Thans_, p. 152. Kohl states that the
peninsula of Diksand on the coast of Holstein consisted, at the close of
the last century, of several islands measuring together less than five
thousand acres. In 1837 they had been connected with the mainland, and
had nearly doubled in area.--_Inseln u. Marschen Schlesw. Holst._, iii,
p. 262.
[315] The most instructive and entertaining of tourists, J. G. Kohl--so
aptly characterized by Davies as the "Herodotus of modern
Europe"--furnishes a great amount of interesting information on the
dikes of the Low German seacoast, in his _Inseln und Marschen der
Herzogthuemer Schleswig und Holstein_. I am acquainted with no popular
work on this subject which the reader can consult with greater profit.
See also STARING, _Voormaals en Thans_, and _De Bodem van Nederland_, on
the dikes of the Netherlands.
[316] The inclination varies from one foot rise in four of base to one
foot in fourteen.--KOHL, iii, p. 210.
[317] The dikes are sometimes founded upon piles, and sometimes
protected by one or more rows of piles driven deeply down into the bed
of the sea in front of them. "Triple rows of piles of Scandinavian
pine," says Wild, "have been driven down along the coast of Friesland,
where there are no dunes, for a distance of one hundred and fifty miles.
The piles are bound together by strong cross timbers and iron clamps,
and the interstices filled with stones. The ground adjacent to the
piling is secured with fascines, and at exposed points heavy blocks of
stone are heaped up as an additional protection. The earth dike is built
behind the mighty bulwark of this breakwater, and its foot also is
fortified with stones." * * * "The great Helder dike is about five miles
long and forty feet wide at the top, along which runs a good road. It
slopes down two hundred feet into the sea, at an angle of forty degrees.
The highest waves do not reach the summit, the lowest always cover its
base. At certain distances, immense buttresses, of a height and width
proportioned to those of the dike, and even more strongly built, run
several hundred feet out into the rolling sea. This gigantic artificial
coast is entirely composed of Norwegian granite."--WILD, _Die
Niederlande_, i, pp. 61, 62.
[318] The shaking of the ground, even when loaded with large buildings,
by the passage of heavy carriages or artillery, or by the march of a
body of cavalry or even infantry, shows that such causes may produce
important mechanical effects on the condition of the soil. The bogs in
the Netherlands, as in most other countries, contain large numbers of
fallen trees, buried to a certain depth by earth and vegetable mould.
When the bogs are dry enough to serve as pastures, it is observed that
trunks of these ancient trees rise of themselves to the surface. Staring
ascribes this singular phenomenon to the agitation of the ground by the
tread of cattle. "When roadbeds," observes he, "are constructed of
gravel and pebbles of different sizes, and these latter are placed at
the bottom without being broken and rolled hard together, they are soon
brought to the top by the effect of travel on the road. Lying loosely,
they undergo some motion from the passage of every wagon wheel and the
tread of every horse that passes over them. This motion is an
oscillation or partial rolling, and as one side of a pebble is raised, a
little fine sand or earth is forced under it, and the frequent
repetition of this process by cattle or carriages moving in opposite
directions brings it at last to the surface. We may suppose that a
similar effect is produced on the stems of trees in the bogs by the
tread of animals."--_De Bodem van Nederland_, i, pp. 75, 76.
It is observed in the Northern United States, that when soils containing
pebbles are cleared and cultivated, and the stones removed from the
surface, new pebbles, and even bowlders of many pounds weight, continue
to show themselves above the ground, every spring, for a long series of
years. In clayey soils the fence posts are thrown up in a similar way,
and it is not uncommon to see the lower rail of a fence thus gradually
raised a foot or even two feet above the ground. This rising of stones
and fences is popularly ascribed to the action of the severe frosts of
that climate. The expansion of the ground, in freezing, it is said,
raises its surface, and, with the surface, objects lying near or
connected with it. When the soil thaws in the spring, it settles back
again to its former level, while the pebbles and posts are prevented
from sinking as low as before by loose earth which has fallen under
them. The fact that the elevation spoken of is observed only in the
spring, gives countenance to this theory, which is perhaps applicable
also to the cases stated by Staring, and it is probable that the two
causes above assigned concur in producing the effect.
The question of the subsidence of the Netherlandish coast has been much
discussed. Not to mention earlier geologists, Venema, in several essays,
and particularly in _Het Dalen van de Noordelijke Kuststreken van ons
Land_, 1854, adduces many facts and arguments to prove a slow sinking of
the northern provinces of Holland. Laveleye (_Affaissement du sol et
envasement des fleuves survenus dans les temps historiques_, 1859), upon
a still fuller investigation, arrives at the same conclusion. The
eminent geologist Staring, however, who briefly refers to the subject in
_De Bodem van Nederland_, i, p. 356 _et seqq._, does not consider the
evidence sufficient to prove anything more than the sinking of the
surface of the polders from drying and consolidation.
[319] The elevation of the lands enclosed by dikes--or _polders_, as
they are called in Holland--above low water mark, depends upon the
height of the tides, or, in other words, upon, the difference between
ebb and flood. The tide cannot deposit earth higher than it flows, and
after the ground is once enclosed, the decay of the vegetables grown
upon it and the addition of manures do not compensate the depression
occasioned by drying and consolidation. On the coast of Zeeland and the
islands of South Holland, the tides, and of course the surface of the
lands deposited by them, are so high that the polders can be drained by
ditching and sluices, but at other points, as in the enclosed grounds of
North Holland on the Zuiderzee, where the tide rises but three feet or
even less, pumping is necessary from the beginning.--STARING, _Voormaals
en Thans_, p. 152.
[320] The principal engine--called the Leeghwater, from the name of an
engineer who had proposed the draining of the lake in 1641--was of 500
horse power, and drove eleven pumps making six strokes per minute. Each
pump raised six cubic metres, or nearly eight cubic yards of water to
the stroke, amounting in all to 23,760 cubic metres, or above 31,000
cubic yards, the hour.--WILD, _Die Niederlande_, i, p. 87.
[321] In England and New England, where the marshes have been already
drained or are of comparatively small extent, the existence of large
floating islands seems incredible, and has sometimes been treated as a
fable, but no geographical fact is better established. Kohl (_Inseln und
Marschen Schleswig-Holsteins_, iii, p. 309) reminds us that Pliny
mentions among the wonders of Germany the floating islands, covered with
trees, which met the Roman fleets at the mouths of the Elbe and the
Weser. Our author speaks also of having visited, in the territory of
Bremen, floating moors, bearing not only houses but whole villages. At
low stages of the water these moors rest upon a bed of sand, but are
raised from six to ten feet by the high water of spring, and remain
afloat until, in the course of the summer, the water beneath is
exhausted by evaporation and drainage, when they sink down upon the sand
again. See _Appendix_, No. 40.
Staring explains, in an interesting way, the whole growth, formation,
and functions of floating fens or bogs, in his very valuable work, _De
Bodem van_ _Nederland_, i, pp. 36-43. The substance of his account is as
follows: The first condition for the growth of the plants which compose
the substance of turf and the surface of the fens, is stillness of the
water. Hence they are not found in running streams, nor in pools so
large as to be subject to frequent agitation by the wind. For example,
not a single plant grew in the open part of the Lake of Haarlem, and
fens cease to form in all pools as soon as, by the cutting of the turf
for fuel or other purposes, their area is sufficiently enlarged to be
much acted on by wind. When still water above a yard deep is left
undisturbed, aquatic plants of various genera, such us Nuphar, Nymphaea,
Limnanthemum, Stratiotes, Polygonum, and Potamogeton, fill the bottom
with roots and cover the surface with leaves. Many of the plants die
every year, and prepare at the bottom a soil fit for the growth of a
higher order of vegetation, Phragmites, Acorus, Sparganium, Rumex,
Lythrum, Pedicularis, Spiraea, Polystichum, Comarum, Caltha, &c., &c. In
the course of twenty or thirty years the muddy bottom is filled with
roots of aquatic and marsh plants, which are lighter than water, and if
the depth is great enough to give room for detaching this vegetable
network, a couple of yards for example, it rises to the surface, bearing
with it, of course, the soil formed above it by decay of stems and
leaves. New genera now appear upon the mass, such as Carex, Menyanthes,
and others, and soon thickly cover it. The turf has now acquired a
thickness of from two to four feet, and is called in Groningen _lad_; in
Friesland, _til_, _tilland_, or _drijftil_; in Overijssel, _krag_; and
in Holland, _rietzod_. It floats about as driven by the wind, gradually
increasing in thickness by the decay of its annual crops of vegetation,
and in about half a century reaches the bottom and becomes fixed. If it
has not been invaded in the mean time by men or cattle, trees and
arborescent plants, Alnus, Salix, Myrica, &c. appear, and these
contribute to hasten the attachment of the turf to the bottom, both by
their weight and by sending their roots quite through into the ground.
This is the regular method employed by nature for the gradual filling up
of shallow lakes and pools, and converting them first into morass and
then into dry land. Whenever therefore man removes the peat or turf, he
exerts an injurious geographical agency, and, as I have already said,
there is no doubt that the immense extension of the inland seas of
Holland in modern times is owing to this and other human imprudences.
"Hundreds of hectares of floating pastures," says our author, "which
have nothing in their appearance to distinguish them from grass lands
resting on solid bog, are found in Overijssel, in North Holland and near
Utrecht. In short, they occur in all deep bogs, and wherever deep water
is left long undisturbed."
In one case, a floating island, which had attached itself to the shore,
continued to float about for a long time after it was torn off by a
flood, and was solid enough to keep a pond of fresh water upon it sweet,
though the water in which it was swimming had become brackish from the
irruption of the sea. After the hay is cut, cattle are pastured upon
those islands, and they sometimes have large trees growing upon them.
When the turf or peat has been cut, leaving water less than a yard deep,
Equisetum limosum grows at once, and is followed by the second class of
marsh plants mentioned above. Their roots do not become detached from
the bottom in such shallow water, but form ordinary turf or peat. These
processes are so rapid that a thickness of from three to six feet of
turf is formed in half a century, and many men have lived to mow grass
where they had fished in their boyhood, and to cut turf twice in the
same spot.
Captain Gilliss says that before Lake Taguataga in Chili was drained,
there were in it islands composed of dead plants matted together to a
thickness of from four to six feet, and with trees of medium size
growing upon them. These islands floated before the wind "with their
trees and browsing cattle."--_United States Naval Astronomical
Expedition to the Southern Hemisphere_, i, pp. 16, 17.
[322] A considerable work of this character is mentioned by Captain
Gilliss as having been executed in Chili, a country to which we should
have hardly looked for an improvement of such a nature. The Lake
Taguataga was partially drained by cutting through a narrow ridge of
land, not at the natural outlet, but upon one side of the lake, and
eight thousand acres of land covered by it were gained for
cultivation.--_U. S. Naval Astronomical Expedition to the Southern
Hemisphere_, i, pp. 16, 17.
[323] _Economie Rurale de la France_, p. 289.
[324] In a note on a former page of this volume I noticed an observation
of Jacini, to the effect that the great Italian lakes discharge
themselves partly by infiltration beneath the hills which bound them.
The amount of such infiltration must depend much upon the hydrostatic
pressure on the walls of the lake basins, and, of course, the lowering
of the surface of these lakes, by diminishing that pressure, would
diminish also the infiltration. It is now proposed to lower the level of
the Lake of Como some feet by deepening its outlet. It is possible that
the effect of this may manifest itself in a diminution of the water in
springs and _fontanili_ or artesian wells in Lombardy. See _Appendix_,
No. 43.
[325] Simonde, speaking of the Tuscan canals, observes: "But inundations
are not the only damage caused by the waters to the plains of Tuscany.
Raised, as the canals are, above the soil, the water percolates through
their banks, penetrates every obstruction, and, in spite of all the
efforts of industry, sterilizes and turns to morasses fields which
nature and the richness of the soil seemed to have designed for the most
abundant harvests. In ground thus pervaded with moisture, or rendered
_cold_, as the Tuscans express it, by the filtration of the canal water,
the vines and the mulberries, after having for a few years yielded fruit
of a saltish taste, rot and perish. The wheat decays in the ground, or
dies as soon as it sprouts. Winter crops are given up, and summer
cultivation tried for a time; but the increasing humidity, and the
saline matter communicated to the earth--which affects the taste of all
its products, even to the grasses, which the cattle refuse to touch--at
last compel the husbandman to abandon his fields, and leave uncultivated
a soil that no longer repays his labor."--_Tableau de l'Agriculture
Toscane._ pp. 11, 12.
[326] _Physikalische Geographie_, p. 288. Draining by driving down
stakes, mentioned in a note in a chapter on the woods, _ante_, is a
process of the same nature.
[327] "The simplest backwoodsman knows by experience that all
cultivation is impossible in the neighborhood of bogs and marshes. Why
is a crop near the borders of a marsh cut off by frost, while a field
upon a hillock, a few stone's throws from it, is spared?"--LARS LEVI
LAESTADIUS, _Om Uppodlingar i Lappmarken_, pp. 69, 74.
[328] Babinet condemns even the general draining of marshes. "Draining,"
says he, "has been much in fashion for some years. It has been a special
object to dry and fertilize marshy grounds. My opinion has always been
that excessive dryness is thus produced, and that other soils in the
neighborhood are sterilized in proportion."
[329] I ought perhaps to except the Mexicans and the Peruvians, whose
arts and institutions are not yet shown to be historically connected
with those of any more ancient people. The lamentable destruction of so
many memorials of these tribes, by the ignorance and bigotry of the
so-called Christian barbarians who conquered them, has left us much in
the dark as to many points of their civilization; but they seem to have
reached that stage where continued progress in knowledge and in power
over nature is secure, and a few more centuries of independence might
have brought them to originate for themselves most of the great
inventions which the last four centuries have bestowed upon man.
[330] The necessity of irrigation in the great alluvial plain of
Northern Italy is partly explained by the fact that the superficial
stratum of fine earth and vegetable mould is very extensively underlaid
by beds of pebbles and gravel brought down by mountain torrents at a
remote epoch. The water of the surface soil drains rapidly down into
these loose beds, and passes off by subterranean channels to some
unknown point of discharge; but this circumstance alone is not a
sufficient solution. Is it not possible that the habits of vegetables,
grown in countries where irrigation has been immemorially employed, have
been so changed that they require water under conditions of soil and
climate where their congeners, which have not been thus indulgently
treated, do not?
There are some atmospheric phenomena in Northern Italy, which an
American finds it hard to reconcile with what he has observed in the
United States. To an American eye, for instance, the sky of Piedmont,
Lombardy, and the northern coast of the Mediterranean, is always whitish
and curdled, and it never has the intensity and fathomless depth of the
blue of his native heavens. And yet the heat of the sun's rays, as
measured by sensation, and, at the same time, the evaporation, are
greater than they would be with the thermometer at the same point in
America. I have frequently felt in Italy, with the mercury below 60 deg.
Fahrenheit, and with a mottled and almost opaque sky, a heat of solar
irradiation which I can compare to nothing but the scorching sensation
experienced in America at a temperature twenty degrees higher, during
the intervals between showers, or before a rain, when the clear blue of
the sky seems infinite in depth and transparency. Such circumstances may
create a necessity for irrigation where it would otherwise be
superfluous, if not absolutely injurious.
In speaking of the superior apparent clearness of the _sky_ in America,
I confine myself to the concave vault of the heavens, and do not mean to
assert that terrestrial objects are generally visible at greater
distances in the United States than in Italy. Indeed I am rather
disposed to maintain the contrary; for though I know that the lower
strata of the atmosphere in Europe never equal in transparency the air
near the earth in New Mexico, Peru, and Chili, yet I think the accidents
of the coast line of the Riviera, as, for example, between Nice and La
Spezia, and those of the incomparable Alpine panorama seen from Turin,
are distinguishable at greater distances than they would be in the
United States.
[331] In Egypt, evaporation and absorption by the earth are so rapid,
that all annual crops require irrigation during the whole period of
their growth. As fast as the water retires by the subsidence of the
annual inundation, the seed is sown upon the still moist uncovered soil,
and irrigation begins at once. Upon the Nile, you hear the creaking of
the water wheels, and sometimes the movement of steam pumps, through the
whole night, while the poorer cultivators unceasingly ply the simple
_shadoof_, or bucket-and-sweep, laboriously raising the water from
trough to trough by as many as six or seven stages when the river is
low. The bucket is of flexible leather, with a stiff rim, and is emptied
into the trough, not by inverting it like a wooden bucket, but by
putting the hand beneath and pushing the bottom up till the water all
runs out over the brim, or, in other words, by turning the vessel inside
out.
The quantity of water thus withdrawn from the Nile is enormous. Most of
this is evaporated directly from the surface or the superficial strata,
but some moisture percolates down and oozes through the banks into the
river again, while a larger quantity sinks till it joins the slow
current of infiltration by which the Nile water pervades the earth of
the valley to the distance, at some points, of not less than fifty
miles.
[332] "Forests," "woods," and "groves," are very frequently mentioned in
the Old Testament as existing at particular places, and they are often
referred to by way of illustration, as familiar objects. "Wood" is twice
spoken of as a material in the New Testament, but otherwise--at least
according to Cruden--not one of the above words occurs in that volume.
This interesting fact, were other evidence wanting, would go far to
prove that a great change had taken place in this respect between the
periods when the Old Testament and the New were respectively composed;
for the scriptural writers, and the speakers introduced into their
narratives, are remarkable for their frequent allusions to the natural
objects and the social and industrial habits which characterized their
ages and their country. See _Appendix_, No. 44.
Solomon anticipated Chevandier in the irrigation of forest trees: "I
made me pools of water, to water therewith the wood that bringeth forth
trees."--_Ecclesiastes_ ii, 6.
[333] One of these, upon Mount Hor, two stories in height, is still in
such preservation that I found not less than ten feet of water in it in
the month of June, 1851.
The brook Ain Musa, which runs through the city of Petra and finally
disappears in the sands of Wadi el Araba, is a considerable river in
winter, and the inhabitants of that town were obliged to excavate a
tunnel through the rock near the right bank, just above the upper
entrance of the Sik, to discharge a part of its swollen current. The
sagacity of Dr. Robinson detected the necessity of this measure, though
the tunnel, the mouth of which was hidden by brushwood, was not
discovered till some time after his visit. I even noticed unequivocal
remains of a sluice by which the water was diverted to the tunnel near
the arch that crosses the Sik. Immense labor was also expended in
widening the natural channel at several points below the town, to
prevent the damming up and setting back of the water--a fact I believe
not hitherto noticed by travellers.
The Fellahheen above Petra still employ the waters of Ain Musa for
irrigation, and in summer the superficial current is wholly diverted
from its natural channel for that purpose. At this season, the bed of
the brook, which is composed of pebbles, gravel, and sand, is dry in the
Sik and through the town; but the infiltration is such that water is
generally found by digging to a small depth in the channel. Observing
these facts in a visit to Petra in the summer, I was curious to know
whether the subterranean waters escaped again to daylight, and I
followed the ravine below the town for a long distance. Not very far
from the upper entrance of the ravine, arborescent vegetation appeared
upon its bottom, and as soon as the ground was well shaded, a thread of
water burst out. This was joined by others a little lower down, and, at
the distance of a mile from the town, a strong current was formed and
ran down toward Wadi el Araba.
[334] The authorities differ as to the extent of the cultivable and the
cultivated soil of Egypt. Lippincott's, or rather Thomas and Baldwin's,
_Gazetteer_--a work of careful research--estimates "the whole area
comprised in the valley [below the first cataract] and delta," at 11,000
square miles. Smith's _Dictionary of the Bible_, article "Egypt," says:
"Egypt has a superficies of about 9,582 square geographical miles of
soil, which the Nile either does or can water and fertilize. This
computation includes the river and lakes as well as sundry tracts which
can be inundated, and the whole space either cultivated or fit for
cultivation is no more than about 5,626 square miles." By geographical
mile is here meant, I suppose, the nautical mile of sixty to an
equatorial degree, or about 2,025 yards. The whole area, then, by this
estimate, is 12,682 square statute or English miles, that of the space
"cultivated or fit for cultivation," 7,447. Smith's _Dictionary of Greek
and Roman Geography_, article "AEgyptus," gives 2,255 square miles as the
area of the valley between Syene and the bifurcation of the Nile,
exclusive of the Fayoom, which is estimated at 340. The area of the
Delta is stated at 1,976 square miles between the main branches of the
river, and, including the irrigated lands east and west of those
branches, at 4,500 square miles. This latter work does not inform us
whether these are statute or nautical miles, but nautical miles must be
intended.
Other writers give estimates differing considerably from those just
cited. The latest computations I have seen are those in the first volume
of Kremer's _AEgypten_, 1863. This author (pp. 6, 7) assigns to the Delta
an area of 200 square German geographical miles (fifteen to the degree);
to all Lower Egypt, including, of course, the Delta, 400 such miles.
These numbers are equal, respectively, to 4,239 and 8,478 square statute
miles, and the great lagoons are embraced in the areas computed. Upper
Egypt (above Cairo) is said (p. 11) to contain 4,000,000 feddan of
_culturflaeche_, or cultivable land. The feddan is stated (p. 37) to
contain 7,333 square piks, the pik being 75 centimetres, and it
therefore corresponds almost exactly to the English acre. Hence,
according to Kremer, the cultivable soil of Upper Egypt is 6,250 square
statute miles, or twice as much as the whole area of the valley between
Syene and the bifurcation of the Nile, according to Smith's _Dictionary
of Greek and Roman Geography_. I suspect that 4,000,000 feddan is
erroneously given as the cultivable area of Upper Egypt alone, when in
fact it should be taken for the arable surface of both Lower and Upper
Egypt; for from the statistical tables in the same volume, it appears
that 3,317,125 feddan, or 5,253 square statute miles, were cultivated,
in both geographical divisions, in the year referred to in the tables,
the date of which is not stated.
The area which the Nile would now cover at high water, if left to
itself, is greater than in ancient times, because the bed of the river
has been elevated, and consequently the lateral spread of the inundation
increased. See SMITH'S _Dictionary of Geography_, article "AEgyptus." But
the industry of the Egyptians in the days of the Pharaohs and the
Ptolomies carried the Nile-water to large provinces which have now been
long abandoned and have relapsed into the condition of a desert.
"Anciently," observes the writer of the article "Egypt" in Smith's
_Dictionary of the Bible_, "2,735 square miles more [about 3,700 square
statute miles] may have been cultivated. In the best days of Egypt,
probably all the land was cultivated that could be made available for
agricultural purposes, and hence we may estimate the ancient arable area
of that country at not less than 11,000 square statute miles, or fully
double its present extent."
[335] A canal has been constructed, and new ones are in progress, to
convey water from the Nile to the city of Suez, and to various points on
the line of the ship canal, with the double purpose of supplying fresh
water to the inhabitants and laborers, and of irrigating the adjacent
soil. The area of land which may be thus reclaimed and fertilized is
very large, but the actual quantity which it will be found economically
expedient to bring under cultivation cannot now be determined.
[336] The so-called spring at Heliopolis is only a thread of water
infiltrated from the Nile or the canals.
[337] The date and the doum palm, the _sont_ and many other acacias, the
caroub, the sycamore, and other trees, grow well in Egypt without
irrigation, and would doubtless spread through the entire valley in a
few years.
[338] Wilkinson has shown that the cultivable soil of Egypt has not been
diminished by encroachment of the desert sands, or otherwise, but that,
on the contrary, it must have been increased since the age of the
Pharaohs. The Gotha _Almanac_ for 1862 states the population of Egypt in
1859 at 5,125,000 souls; but this must be a great exaggeration, even
supposing the estimate to include the inhabitants of Nubia, and of much
other territory not geographically belonging to Egypt. In general, the
population of that country has been estimated at something more than
three millions, or about six hundred to the square mile; but with a
better government and better social institutions, the soil would sustain
a much greater number, and in fact it is believed that in ancient times
its inhabitants were twice, perhaps even thrice, as numerous as at
present.
Wilkinson (_Handbook for Travellers in Egypt_, p. 10) observes that the
total population, which two hundred years ago was estimated at
4,000,000, amounted till lately only to about 1,800,000 souls, having
been reduced since 1800 from 2,500,000 to that number.
[339] Ritter supposes Egypt to have been a sandy desert when it was
first occupied by man. "The first inhabitant of the sandy valley of the
Nile was a desert dweller, as his neighbors right and left, the Libyan,
the nomade Arab, still are. But the civilized people of Egypt
transformed, by canals, the waste into the richest granary of the world;
they liberated themselves from the shackles of the rock and sand desert,
in the midst of which, by a wise distribution of the fluid through the
solid geographical form, by irrigation in short, they created a region
of culture most rich in historical monuments."--_Einleitung zur
allgemeinen vergleichenden Geographie_, pp. 165, 166.
This view seems to me highly improbable; for though, by canals and
embankments, man has done much to modify the natural distribution of the
waters of the Nile, and possibly has even transferred its channel from
one side of the valley to the other, yet the annual inundation is not
his work, and the river must have overflowed its banks and carried
spontaneous vegetation with its waters, as well before as since Egypt
was first occupied by the human family. There is, indeed, some reason to
suppose that man lived upon the banks of the Nile when its channel was
much lower, and the spread of its inundations much narrower than at
present; but wherever its flood reached, there the forest would
propagate itself, and its shores are much more likely to have been
morasses than sands.
[340] _Memorie sui progetti per l'estensione dell' Irrigazione, etc., il
Politecnico_, for January, 1863, p. 6.
[341] NIEL, _L'Agriculture des Etats Sardes_, p. 232.
[342] NIEL, _Agriculture des Etats Sardes_, p. 237. Lombardini's
computation just given allows eighty-one cubic metres per day to the
hectare, which, supposing the season of irrigation to be one hundred
days, is equal to a precipitation of thirty-two inches. But in Lombardy,
water is applied to some crops during a longer period than one hundred
days; and in the _marcite_ it flows over the ground even in winter.