Of the Thurmberg, Humboldt remarks that it is the most remarkable

elevation between the Hartz and the Ural Mountains, and that but a few

points in the Valdai range can be brought into comparison with it. Its

position close by the sea is especially noteworthy. It is very probable,

according to Humboldt’s opinion, that those inequalities of surface,

formed of sand once partly or wholly submerged,—found in Mecklenberg,

Pomerania, East Prussia Proper,—and now divided into flats and hill

ranges, do not belong to the dune system of the ancient shore-line, but

have the reason of their existence in ordinary upheaval; in the formation

of limestone, and of the usual Jurassic rocks, which, afterward,

have been covered with sand and other loose materials. The peculiar

accumulation of genuine marine fossils indicates the existence of

upheaved rocks below the upper layer of sand.

It is these elevations which in the constantly advancing ridge or ridges

run northeasterly, and take the form of plateaus, increasing in breadth

from the water-shed north of Smolensk, and the source of the Dnieper, in

the Valdai Forest, and the western Uwalli, and which are found between

the Volga and the Dwiner, and thence run eastward as far as Perm, on

the Kama. They form the line of demarkation between the great Central

European plain and the North Russian lowland, which extends as far up as

the Arctic. This easterly chain, so far as it has been measured, seems

to be less in altitude than the Valdai hills, which are about 1000 feet

high. In East Prussia Proper and Livonia there are elevations of more

than 600 feet; about 55 miles south of Dorpat Munnamäggi, the point of

culmination, according to Struve, is 996 feet above the sea; south of

Vilna the heights of Puzewitch reach an elevation of 990 feet.

In the same direction, still northeast, runs the Valdai, forming the

source of a number of large streams and the great water-shed of eastern

Europe. On the road from St. Petersburg to Moscow, Humboldt found the

altitude at Norwaja Ijetza 660 feet, and the highest point at Popowa Gora

792 feet, (according to Pausner, 876 feet.) One point going south from

the Valdai, at Mosti Derewna, the latter naturalist has ascertained to be

1032 feet above the sea; and the highest point in the range is, according

to Helmersen, 1098 feet. Still further eastward, between the Valdai hills

and the lake region between Lake Seligher and Bielo Ozero, the range of

uplands, known as Uwalli, running northwesterly, intersected by numerous

canals, and forming the water-shed of a number of rivers, gradually

diminishes in height, but, still advancing eastward, it rises again, in

the neighborhood of Perm and the Kama, to 1014 feet,—about the elevation

of the Valdai range. Uwalli is only the Sclavic name of such hills as

those whose absolute height is insignificant, but which, crossing as

they do the great plains of Poland, Lithuania, and Russia, were formerly

confounded with mountain ranges, and were so represented on the maps.

They have, of course, great hydrographical value, and play a leading part

as the water-shed of eastern Europe.

The Ponto-Caspian Plain, the Great Depression of the Old World.

This second vast lowland is the direct continuation of the central

European lowland, with a decided sinking toward the Black and the Caspian

Seas, indicated by the course of the rivers of that region. It extends

from the month of the Danube over the lower Dniester, Bog, Dnieper,

Don, and Volga, as far eastward as the Sea of Aral. To the last named

the Siberian plain gradually declines. The southern plain of Europe

stands in unbroken connection, so far as its formation is concerned,

with the West Siberian plain, (2,213,400 square miles in extent,) and

is, therefore, one of the most extensive lowlands on the globe. The

Baltic-Sarmatian plain is separated from the West Siberian merely by the

long Ural chain, (from 50° to 67° N. lat.,) whose elevation is only from

4000 to 5000 feet, and whose breadth is unimportant. Take away the Ural,

and a continuous line could be drawn from Breda, near the confluence

of the Meuse, Rhine, and Scheldt, across Europe and Asia, following

the line of 50° N. lat as far as the Chinese frontier, passing over a

continuous series of low, insignificant hills, heathlands, and steppes,

and traversing a space estimated by Humboldt to be three times the length

of the Amazon!

Toward the south, the Cis-Ural, European side of the Ponto-Caspian

lowland, is separated from the Black Sea by a ridge of granite knolls,

which passes from Volhynia and Podolia eastward as far as the cataracts

of the Dnieper, and thence southeast, with diminished breadth, reaching

its limit at Taganrog, on the lower Don, and the Sea of Azof. This ridge

separates the narrow steppes of the northern shore of the Black Sea

from the lowland of South Russia, the fruitful district of Ukraine. The

height of these hills in the west, where they appear to have the greatest

elevation, has been estimated to be about 1000 feet above the sea. Toward

the Dnieper they have not yet been carefully measured; but probably there

they do not rise above 700 feet.

The small sand steppe south of these granite hills runs from the Crimea

eastward as far as the North Caucasian steppe, between the Don, Volga,

and the Caspian, and indeed may be traced to the northeast as far as

the Bashkiric-Ural chain. Lakes of marked saltness are found there:

Elton, for instance, which lies 24 feet above the sea; while farther

eastward they are found, as for example on the Kamysh and at Samara at a

depression of—138 feet, 60 feet below the level of the Caspian Sea. Yet

this lacks confirmation.

From this lowland, only a few elevations arise, and these of

insignificant absolute height; yet, on account of the extreme uniformity

of the whole country, they are objects of amazement to the whole steppe

world. The Little Bogdo, south of Lake Elton, and yet farther south,

Great Bogdo, 504 feet above the sea, according to Humboldt, and Mount

Arsargar, 331 feet in absolute height, according to Murchison, are the

only important hills. The Great Bogdo is composed of calcareous limestone

and of sandstone, with rich deposits of salt.

The Kirgheez steppe separates, by a plain of very moderate elevation, the

north Siberian lowland from the Caspian-Ural depression. It was formerly

supposed, and indeed represented on the map, that a mountain range passes

through this district from the Ural chain to the Altai. The Kirgheez

steppe appears to range from 780 to 960 feet in elevation; while the

Siberian plain is but 280 feet above the sea at Omsk, 192 feet at Tora,

and 108 feet at Tobolsk. It has been considered by some that the Kirgheez

steppe, as well as the granite hills of southern Russia, belong to an

undeveloped system of mountains, an early cooling having solidified them

before reaching the elevation which they would have attained; and that

they partake of the direction which analogy would teach us such a chain

would have, from northeast to southwest, parallel with the Carpathian and

the Caucasus ranges.

The great depression of the Old World begins with the deepening of

the Volga basin below Simbeersk; and at the place (51¾° N. lat., near

Orenboorg and Saratov) where it breaks through the last row of hills in

the Obstshei-Syrtis, it commences a rapid descent toward the Caspian and

the Aral Seas. This great concavity, on the confines of Europe and Asia,

at the center of the greatest land-mass, and far removed from any ocean,

is remarkable as having no parallel on the globe. Humboldt remarks that

perhaps a similar phenomenon would be repeated at the interior of other

continents, if the tertiary formation and the parts found by marine

deposit did not exist. It would be profitable to follow out so weighty a

thought, with the surface as it now is.

The Obstshei-Syrtis is the moderate range of hills which runs westward

in two branches from the Bashkiric-Ural, at Orenboorg, the northern spur

running by Uralsk and the Ural River; the southern by Samara, rising

on the east shore of the Volga to a height of 600 feet, and ending at

Sarepta.

Orenboorg, on the Obstshei-Syrtis, where it leaves the Ural chain, is 255

feet above the sea. Uralsk lies somewhat lower, being 234 feet above the

sea. The surface of the Volga, where it breaks through the high banks of

Saratov, is only 36 feet above the ocean level; while the western shore,

above Saratov, is 562 feet in height. Farther down the river, Sarepta

lies 30 feet below the sea level; and there is, therefore, between

Saratov and Sarepta, a distance of about 180 miles, a fall of 66 feet.

West of the Volga, and following the river, is the continuation of the

Obstshei-Syrtis, ranging in elevation from 562 feet down to 168 feet.

At Sarepta, the low hills which thus far have skirted the Volga turn to

the southwest, to the Manitsh steppe, sinking to an elevation of but 75

feet, and extending as far as the Sea of Azof. At Sarepta, too, the Volga

turns from its normal southerly course, and strikes southeasterly across

the Astracan steppe, entering the Caspian at the City of Astracan, 72

feet below the level of the sea. The level of the sea is 4 feet below the

shore on which Astracan is built.

The old statements that the level of the Caspian is 300 feet below the

ocean, rested solely on conjectures made by the naturalist Pallas. The

influence of this great depression on the warmer climate of that region,

the peculiar vegetation of the salt steppes, and the salt morasses which

exist where the land is perfectly level, as well as the great beds of

oyster-shells and other crustaceous remains, led him to the hypothesis

that the whole neighboring district is the dry and deserted bed of a

former sea, now shrunk to the comparatively insignificant dimensions

of the Caspian. The broken line of bold bluffs which bounds the

Obstshei-Syrtis on the south seemed to him to be the northern boundary of

this inland sea, into which the Volga entered below the pass of Kamyschin

and Saratov. Parrot and Engelhardt supposed that their barometrical

elevations in 1811 confirmed Pallas’ theory, that the Caspian lies 300

feet below the ocean. Many hypotheses were based upon their observations;

but the whole were at length brought into discredit by Humboldt, who

distrusted the accuracy of instruments made at that time. Nothing but a

trigonometrical survey from Taganrog to Astracan could give conclusive

results, and this was accomplished in 1837, under the auspices of the

Russian government. The result proved that, so far from being 300 or 350

feet below the ocean, the Caspian is not 100 feet. Its depression, as

already stated, is about 76 feet.

The level of the Aral Sea, which is evidently closely linked to

the Caspian, has not yet been determined with absolute certainty.

Barometrical observations were instituted for this end by the expedition

under General Berg, which explored that region in the winter of 1826,

but the cold was severe, and the results are questionable. The result of

their investigations was, however, that the surface of the Aral lies 110

feet higher than that of the Caspian. This would make the Aral to be 34

feet above the sea level. More careful inquiries may, however, determine

the level of the two seas to be the same; but at present we have to be

content with the results of the expedition referred to, and accept its

elevation as 34 feet above the level of the ocean.

Without, however, going into details respecting the Aral, the region

around the Caspian and directly connected with it, which is below the

ocean level, embraces an area of not less than 131,400 square miles. This

survey extends from the Volga to the Ural River, thence to the Emba and

the northernmost point of the Sea of Aral, and thence to the salt lakes

of Aksakal-Barbi, lying to the northeast of this sea. The tracing of

this line from the higher to the lower stages of depression gives clear

indications, in the nature of the soil, of the existence of a great sea

once occupying that whole tract.

Thus much for the configuration of the Caspian lowland. If to these

131,400 square miles be added the 153,000, or, according to Humboldt,

164,000 square miles of the Caspian itself, the entire depression

embraces almost 318,000 square miles, and is greater than France,

greater than Germany, and only to be compared with the whole Austrian

empire! If to this great region be added the district around the Aral,

which sea alone covers nearly 25,000 square miles, and then to this the

yet unmeasured surface covered by seas yet to the eastward, the entire

region of depression is immensely increased. And then if to this be added

the great Siberian plain, whose level is not greatly above the sea, the

combined district would be at least once and a half as great as all

Europe.

The Origin of the Ponto-Caspian Depression.

Thinking of the immense extent of this depressed region, whose entire

surface occupies no inconsiderable fraction of the interior of the Old

World, and whose greatest depth at the bottom of the Caspian is from

500 to 600 feet below the level of the ocean, and looking at it as a

phenomenon wholly unique, the question arises: How would such a condition

be possible, contradicting, as it seems, all analogies? The answer, could

we reach it, would not fail to illustrate many recondite geological

questions, and to be full of instruction.

Yet the time has not come when a full answer can be given to this

inquiry. We have not yet learned the elementary conditions of this

remarkable fact; there are innumerable investigations yet to be made,

before we can feel perfectly certain that its reason is understood.

Still, there have been some preparatory inquiries entered upon, and some

preliminary steps taken toward reaching a conclusion, or, at least,

toward assuming a reasonable hypothesis. We have already indicated our

belief that this depression is connected with a ring of plateaus which

have been upheaved around it, and which now inclose it and isolate it

from the ocean.

The hollow has its greatest depth near the southern extremity of the

Caspian, where it rises abruptly to the Persian plateau. There pass, in

the form of a half circle, the loftiest mountains and plateaus of central

Asia. On the west side the Caucasus rises, with its giant peaks of

Kasbek and Elbrooz, 15,000 to 17,000 feet high, bearing all the marks of

volcanic origin,—avalanches of solidified lava on the sides, a lake lying

in the abyss of an extinct crater, and the like.

At the southwest, the Armenian plateau follows the course of the Aras

from its mouth back to the huge dome of Ararat, 14,656 feet high. The

entire geological appearance of that region—the old lava streams, the

trachyte rocks—indicate with equal clearness, as in the Caucasus, the

agency of volcanic forces in the upheaval of that district. Traces of

this great power are also seen in the caldron-shaped hollows, and in the

narrow and deep defiles, which are abundant in that region.

South of the Caspian, which in its southern part reaches a depth ranging

as low as 420, 480, and 600 feet, and, according to Hanway, even 2700

feet, rise sharply from the sea the Persian Coast Mountains. The plateau

of Teheran, 3400 feet in elevation, is directly beyond, from which rise

the volcanic peaks of Demavend, 20,000 feet, and Euczan, 6600 feet high.

The Coast chain embraces the Elboorz Mountains, uniformly more than

5000 feet high, but which, at Schemrum, northwest of Teheran, rise to

a height of 8560 feet; at Churchurah, southwest of Demavend, to 7650

feet; at Nevo, southeast of Demavend, to 8540 feet; at Nejoster, in the

Seriakush, east of Demavend, to 7200 feet; and which, above Asterabad,

rise in the Shahkush and the Sundukkush to a height of 7270 feet, and

almost everywhere display in their trachyte rocks the traces of ancient

volcanic activity. Still farther to the east, the chain which has girdled

the Caspian sinks from the lofty height of the Northern Taurus to 1872

feet; in Meshed, 2628 feet; in Herat, an average elevation of 3400 to

4000 feet. But east of Herat it rises abruptly to the lofty plateaus of

Bamian and Cabool, 7000 and 8000 feet high, and in the peaks of Colubeba

16,800 feet. The Hindoo Koosh, at Dsellalabad, rises to a height of

18,984 feet; the table-lands of the Bolor, at the Issikul, are at an

elevation of 14,664 feet; while the gigantic Pameer is not yet measured,

though its noted Pass is estimated at 18,000 feet above the sea.

At this point we reach almost the 40th degree of N. lat., whence

northward the mountain ranges gradually decline in height, after

throwing off eastward the great chain of Thian-Shan. From the sharp

angle formed by the Hindoo Koosh and the Bolor, where the head-waters

of the Gihon rise, that large but commercially unimportant river takes

its way westward through the Bokharan table-land, falling so rapidly

in its course to Bokhara that at the city its surface is but 1116 feet

above the sea, then striking northwesterly to the Aral and Caspian. The

course of that stream indicates, therefore, the direction and degree of

the mountain slope toward the great depression east of the Caucasus and

Armenia, north of the Persian highland, and west of the Hindoo Koosh and

the Bolor systems.

The lower course of the Gihon, from Bokhara downward, is through masses

of mud, sand, and gravel, and can very easily be conceived to have

changed its course in the lapse of centuries, from the Caspian to the

Aral, as the course of the Sihon seems also to have changed. The great

Bokharan plain is covered in this part with a deposit of dried mud; it is

a steppe formed evidently from a now dry sea-basin, which, no less than

the northern shores of the Caspian and the Aral, displays the traces of

the oceanic character of entire regions.

Halley, the astronomer, made an attempt to solve the mysterious origin of

this great sunken basin, and attributed it to the stroke of a first-class

comet! Arago, instead of calling into the scene meteorological forces

little known, contented himself, in his theory of its origin, with the

forces which we know are active even now on the earth, the plutonic

powers which are only half confined by the surface of the globe. No

one, he says, will hesitate now to accept the upheaval theory, through

which geology is able so clearly to indicate the forces and progress of

structure of the soil and rocks. The upheaval of great masses in one

place predisposes the depression of districts in their neighborhood, to

make good the true relation of highland to lowland. And in this case a

compensation may be found, according to Arago, for the great semicircle

of mountains which passes around the southern margin of the Caspian

basin, in the depression caused by the natural falling in of the adjacent

region when the great mountains of western Asia were upheaved.

In longitudinal mountain chains the parallel ranges of valleys have

a similar origin; in volcanic chains, which have been thrown up in

a circular form, similar depressions have been found in the middle,

although, it must be confessed, on a much smaller scale of dimensions

than in the Caspian hollow. The same feature is observable in the

upheavals, by Von Buch, as observed in the Island of Palma, one of the

Canaries, or in the Val di Bove, near Etna. Such depressions would at

once fill with water, if connected with the sea, as in the cup-shaped

island Santorini, or remain land-locked, if they occur in the interior,

as in the case of Lake Laach, as the half-ring of mountains girding the

lower portion of the Caspian seems to consist mainly of trachyte thrown

up by volcanic agency: the analogy just drawn does not seem too remote.

Yet the process of structure must have had other concomitant conditions

to account for the vast reach northward of the Caspian depression. It

is clear that any such volcanic convulsion as would throw up those vast

mountain ranges at the south, must have affected largely the geological

condition of all the adjacent region; the extent vertically of this

effect would be best ascertained perhaps by deep boring. Unquestionably

there was many a revolution in the upper portions of the earth’s crust

during the formation of the great Caspian hollow, before it assumed its

present condition. From the agencies at work in connection with a great

internal ocean, the upper soil, as we have it to-day, was formed.

The Aral and the Caspian Seas remain as the lowest places of that great

depression, water being found in them, while elsewhere it has entirely

disappeared by evaporation: leaving us broad, low plains, instead of that

great ocean which once extended from Persia over all Siberia, and west

of the Caspian to the Sea of Azof. A more thorough account, geographical

as well as geological, cannot be given till after much more extended

investigations have been made into the physical characteristics of this

region than as yet have been prosecuted. It may be remarked here, that

the waters of the Aral and Caspian are bitter and salt, but not so much

as those of the ocean; the bottom is covered with slime and sand. The

Aral has a depth ranging from 90 to 222 feet; the Caspian, beginning

with its extensive, shallows at the north, deepens toward the south,

till, reaching the lower third, its depth is over 600 feet; and thence

southward it is no less deep, till it reaches the bold shore of Eusellis.

From this lowest point the upheaval begins, which culminates in the great

mountains on its southern border.

According to Humboldt’s view, the great Caspian hollow embraces not only

the basin of the sea, but a vast dry plain, extending northward as far as

Saratov and the Obstshei-Syrtis; even Uralsk lies lower than the level

of the Black Sea. The same physical feature, though on a less extended

scale than here, is found in Holland, China, Lower Egypt, and Palestine.

Subsequently to the emergence of the continents, long before the filling

in of huge fissures by mountain chains, and during the continuance of

those great convulsions which reach back into the remotest geological

periods, the surface of the continents must have been subjected to

frequent partial changes of level. The surface undulated probably in that

same wave movement which is now observable, though in much less degree,

in those earthquakes and upheavals which the whole western part of South

America is experiencing even now.

The depressions which have assumed a permanent form since the convulsions

which formed them, have gradually filled with deposited soil, and, were

the naturalist able to lay bare the primitive rock, he would discover

that it exists in the shape of great concavities, without a trace of

that evenness which now characterizes the surface. Eichwald has made

it probable, by his personal observations, that the upheaval of Ararat

and of the Armenian plateau on which this trachyte mountain rests, has

driven the Caspian Sea back east of the flat steppe of Karabagh and

Mogan, on the lower Aras, to the neighborhood of Bakoo. The water of

that sea formerly extended to the confluence of the Bargashad, (called

also Bergershat and Bergernet,) with the Aras, below Ireben. The traces

of volcanic action there are decisively evident: the Caspian reached,

before that action occurred, up what is now the valley of the Aras, as

far as Ararat; and in many places south of Erivan—at Saliyan, in Shirwan,

and elsewhere—salt beds of the most crystalline quality, forming whole

mountains and whole belts of salt lakes at the confluence of the Aras and

the Koor, demonstrate their formation in a former sea which once covered

that region. The very recent upheaval of the Ural chain cannot fail also

to have had an influence in contracting the dimensions of the Caspian

hollow.

Only two kindred depressions to this remain to be spoken of, which,

though of not so great superficial dimensions, are of yet greater

depth—the depression of the Jordan Valley and the bitter salt lakes on

the Isthmus of Suez. These we must consider before we pass from the

contrasts between highlands and lowlands to the transitions between them.

The Depression of the Jordan Valley and of the Dead Sea.

The nearest relationship to the Caspian hollow, displayed by any similar

feature, is found near the heart of the Old World, in the comparatively

diminutive and isolated valley of the Jordan, including the Dead Sea,

whose absolute depth below the level of the ocean has been determined

only within the most recent period. Many former travelers had noticed, in

the deep gulf which holds the Dead Sea, and especially at its north end,

near Jericho, a much greater degree of heat than elsewhere in Palestine,

and the existence of many plants and fruits which they had met in the

hotter climates of Arabia and India. The tree which yields the Mecca

balsam flourishes in the oasis of Jericho; the product of the balsam

of Palestine supplied the pin-money of Cleopatra. A number of German

and English observers endeavored to solve the question of the depth of

the Jordan basin—von Schubert, Russeger, von Wildenbruch, Moore, and

Bake, later Symonds, and Lynch; de Berton and Russeger made the first

barometrical observations at the Dead Sea, but they did not attempt

to give more definite limits to their results than to assert that its

surface is somewhere between 500 and 1100 feet beneath the ocean level.

Von Shubert’s barometer did not suffice to determine this point, but he

ascertained the surface of Lake Tiberias to be 535 feet below the surface

of the Mediterranean. All barometrical measurements were unreliable at

that depth; yet it could not be denied that the depression could not be

an insignificant one. A measurement with the level made by Symonds, an

Englishman, from Jaffa to the Dead Sea, in 1843, gave us our first sure

results. The surface of the lake lies 1231 feet beneath the level of the

Mediterranean at Jaffa. The subsequent expedition of the Americans—Lynch,

Dale, and Anderson, in 1848—has given the following additional results:—

The surface of Lake Tiberias lies beneath the ocean level, 612 ft.

” ” the Dead Sea ” ” ” 1235 ”

Soundings of the Dead Sea, made with the greatest care, determined the

depth to be, according to Lynch, 1227 feet; according to Symonds, 1970

feet. The entire depression below the ocean level would be, then, by

Lynch’s measurement, 1235 + 1227 = 2462 feet; according to Symonds’, 1235

+ 1970 = 3205 feet. This is the greatest known depression on the globe.

Jerusalem lies 2449 feet above the ocean level. From the roofs of the

city to the surface of the Dead Sea is, therefore, 2449 + 1235 = 3684

feet; and the entire descent from the capital to the bottom of the Dead

Sea is 4911 feet, if we adopt Lynch’s measurement, and 5654, if we follow

Symonds’.

The basin of the Dead Sea consists of two very different parts—the larger

and deeper northern one, the smaller and shallow southern one; the two

being separated by a sandy peninsula—el Mesraa—and connected by a narrow

channel of insignificant depth. The northern basin seems to owe its

present form to the unchanged primitive depression; the southern one

to a partial upheaval at some later epoch. But in breadth they do not

vary much one from the other; both have their larger axis coincident

with the Jordan valley, which here widens a little, but which is still

hemmed in here, as farther north, by the parallel ranges of mountains.

The chain east of the sea appears to rise a thousand feet higher than

the one west of it. The depths of the two basins are entirely unlike.

The southern is nowhere more than 12 feet deep, and diminishes to 5 feet

and less than this near the shores, so that the southern half of it is

entirely unnavigable by craft of any size; and those who wish to land

have to wade for a long distance through mud as deep as their ankles.

The northern part, on the contrary, attains a uniform depth of more than

1000 feet, from the north to the south; in the northern third it is even

1227 feet; toward the west coast it shoals to between 600 and 800 feet,

but is 500 feet deep hard-by the coast. There is but a very narrow rim

of shallow water on the western side, and the navigation is, therefore,

tolerably safe. On the eastern shore the coast is even bolder, and the

descent to deep water immediate. Close by the romantic mouth of the

Arnon, embouching through rocks, the depth of the sea is about 1052 feet.

So great a difference in the depth of the two basins seems to indicate a

considerable diversity in the manner of their formation.

Volcanic activities have been felt in the Jordan valley up to the present

time. They manifest themselves in various forms—deposits of salt, hot

springs and naphtha springs, asphaltum beds, sulphur fumes, currents

of heated air, clouds of smoke, and rumblings beneath the surface.

The Jordan valley remained, from Lake Tiberias down, unfilled, as we

should infer from analogy that it would be by the upheaval of a chain

of volcanic mountains; or by the expansion of an internal lake or sea,

the waters accumulating till at last they should acquire such volume as

to break away and form new channels. In case the obstructions were too

great, they would remain inland lakes. And such is the Dead Sea, its

southern border being too high to allow it a free exit into the Red Sea.

Many other fissures or hollows on the surface of the continents would

be regarded as lowlands, were they not filled with water. The bottoms

of such lakes often sink suddenly to a great depth, while others are

lagoon-like, or shallow seas of an entirely different hydrographical

character. Internal lakes, regarded as isolated lowlands, merely filled

with water, are an especially interesting theme of study; yet much

remains to be investigated regarding their structure and historical

formation. The Dead Sea has been regarded, up to this time, as the

deepest of all such lakes. The greatest depth of the Caspian has not yet

been fully ascertained; but if Hanway’s soundings, 2700 feet, are to be

relied on, it is very great. Lake Baikal, in its deepest part, between

the two steep walls of rock which rise high above the surface, has not

yet been carefully sounded; but as its surface is 1500 feet above the

sea, its bottom does not probably fall below the ocean level. The great

chain of North American lakes, whose area embraces about 109,500 square

miles, are surrounded by level country from 500 to 600 feet above the

sea—a region which, in part, falls under the designation of plateaus of

the lowest class, and which, in part, comes under the name of lowland;

the surface of Lake Superior being 627 feet above the sea, Lakes Michigan

and Huron 578 feet each, Lake Erie 565 feet, and Lake Ontario 232 feet.

The three first named, having a depth of about 900 feet, have their beds

about 300 feet below the surface of the ocean; Lake Ontario, with a depth

of 500 feet, reaches a point 268 feet below the sea level. The depth of

the St. Lawrence river bed, as related to the sea, is not ascertained.

The most of the Swiss lakes, too, having a depth often of more than 1000

feet, come under the same category with the lakes under consideration

above, waters from the mountains having gradually filled up chasms made

at the time of the upheaval of the adjacent region. Some of these lake

basins may be deep enough to lie below the level of the ocean.

The Bitter Lakes of the Suez Isthmus.

Some bitter salt lakes on the Isthmus of Suez, forming a chain from

the Red Sea to the southeast corner of the Mediterranean, long claimed

attention from their supposed singularity. During the occupation of

Egypt by the French in 1799, a survey of the district was made with the

level, in view of a prospective canal across the isthmus, connecting

the Nile with the Red Sea. An account of that survey was published

by Le Père, in his great Description de l’Egypte. The result of the

survey was very surprising; it assigned to the Gulf of Suez a height of

25 feet at ebb tide and 30½ feet at flood tide, above the level of the

Mediterranean, a result which seemed to agree with Pliny’s account (vi.

23) of the elevation of the Red Sea above the level of lower Egypt. The

salt swamps lying between the two seas, and known even to the ancients,

lie, according to the same authority, 20 feet below the surface of the

Mediterranean, and 50 feet below that of the Red Sea. These singular

statements were not received without considerable doubt as to their

correctness; but during the military disturbances in that region, no

revision of the investigations could be made. Certain circumstances

connected with an unusual inundation of the Nile in 1800, when its waters

flowed as far as the transverse valley called the Wady Tumilet, in which

the salt lakes lie, and where traces of the ancient canal, built by the

Egyptians between the seas, could be seen, seemed to confirm the result

of the survey of 1799. The inference was a natural one—that the sandy

Isthmus of Suez was an accumulation of dunes, and of the deposits of

inundations of both the Mediterranean and Red Seas, and that the salt

morasses in the middle are but a trace of the primitive bottom. There

were not wanting defenders of the old measurement, Favier being the most

prominent. Since 1845 five surveys have been made, in reference to the

projected canal. These all contradict the results of 1799, and show that

there is but the difference of four-sevenths of a foot between the level

of the two seas, and that there is the same agreement there as in all

other parts of the earth. Many hypotheses, built on the old measurement,

have accordingly fallen to the ground.

The Regions of Transition between Highlands and Lowlands; the River

Systems of the Globe.

Between the two great and most sharply-marked physical features—the high

plateaus and mountains and the lands of very little elevation—there are

regions of transition very numerous and exceedingly varied.

The conception of highlands and of lowlands having a certain, constant,

and absolute value, and it being immaterial whether the elevation

be specially marked or not, provided it be uniform, the regions of

transition find their most marked characteristics in their want of

constancy, in their very change, and the rate at which the grade ascends

from a low to a high elevation, or falls from a high to a low one. Their

real value lies in the mutual compensation of highlands and lowlands,

which is effected through the mediation of a third physical feature or

system, which has received the name Lands of Gradation, or Terrace Lands,

and which, by their gradual rise from the sea level, serve as the means

of transition from the lowest lowlands to the loftiest plateaus and

mountains.

Terrace Lands and Rivers in their General Character.

Districts sloping to the sea, or lands of gradation, as we have called

them, varying as they do in elevation and in relative situation to

each other, are the true mediators between the districts but little

above the level of the sea and others much more lofty. At the sources

and the mouths of rivers they partake, more or less fully, in the

characteristics of both highland and lowland. The manner of their

mediation, as determined by the rate of the fall of water and by their

direction, gives to every one of these regions of transition its

peculiar character, determines its conformation and its relation to

the globe. And yet, no more than in lowlands and highlands, can we rid

ourselves of some arbitrary data relating to the size of rivers, when

we discriminate between those which we call large and those which we

call small. As in all other geographical distinctions, we must here

be content with arbitrary approximation, and with the ordinary usages

of speech. The comparison of streams, in regard to their breadth and

fullness, determines their volume; the comparison, in respect of length

and tributary waters, determines the compass of the river system. The

entire characteristics, breadth, depth of channel, length and extent

of drainage, determine the status of the river, whether first, second,

or third class, in relation first to those of the same continent, and

then to those of the world. The Volga, for instance, is, in relation

to Europe, a first-class river, but, like the Danube, in relation to

the entire globe, is merely in the second or third rank. Not the length

alone determines the importance of rivers. The Thames, one of the

smallest streams in Europe, is one of the most important. And aside from

commercial considerations, a river of insignificant size can have great

influence in consequence of its relation to the entire adjacent region.

The little Bavarian Isar, a river which, so far as the great world is

concerned, seems to have no importance, receives on the left side the

water of 860 tributary brooks, among which are 44 rivulets; on the right

bank the water of 433: these 1293 brooks and rivulets pour themselves

into the Isar through 103 direct tributaries, and not these alone, but

the waters of 136 lakes are embraced within the Isar system! Yet the Isar

is only one of 34 branches of the Danube, and of the fourth rank even

among them, and the Danube is by no means one of the great rivers of

the globe. A short but navigable stream can have great influence over

a territory limited in extent, and may make a long but shallow stream

sink into insignificance in respect of comparative importance to the

world. There are some great streams which are of first magnitude in all

their characteristics—rivers which drain millions of square miles in

their course to the sea. The number of such is small, however; there are

scarcely fifty on the whole globe. Besides these, there is a large number

of rivers much shorter, and of much less volume, but not deficient in the

attributes which give a stream value to man, and which serve to mediate

between highlands and lowlands, to fulfill the needs of navigation and

to drain regions of more or less magnitude. These can be classed in four

ranks: in the first place absolutely, and in the second place in relation

to each continent. Yet, in classing them, it is necessary always to keep

in mind that it is not size alone which gives a river its value, but a

combination of all its characteristics, and its relative influence on the

country through which it runs.

Looking at the direction of streams, we observe that there are some which

flow northerly, as for instance those of Siberia, the Nile, the Rhine,

the Elbe, and the Weser; there are those which flow southward—the Indus,

Ganges, Euphrates, La Plata, Mississippi, and Volga, for example; there

are those flowing eastward—Hoang-ho and Yang-tse-Kiang, the Amazon, the

Orinoco, and the Danube, for instance; and some westward, instances of

which may be found in the Gihon and Sihon, the Senegal, Gambia, Niger,

the Colorado, the Seine, Loire, Garonne, and the Spanish rivers which

enter the sea in Portugal.

And this characteristic, trite and unmeaning as it may at first seem,

establishes, for the area which these rivers water, very diverse

conditions. In like manner, too, their position, in relation to the

oceans into which they flow, is very influential, in consequence of

the action of the tide upon the lower course. The emergence of their

head-waters at various altitudes, whether on plateaus of the first or

second class, or on mountain tops covered with perpetual snow, gives rise

to a great diversity of relations, that makes no one stream on the earth

twin brother to any other. Rivers have an individuality which claims

recognition, although they are usually summed up in one category.

This diversity in rivers becomes more apparent from a study of the

diversified form of the terraces, or grades of transition, through which

they pass on their way to the sea.

The great basin of the Nile is divided into three distinct parts or

grades—Abyssinia, Nubia, and Egypt; and each of them has long been

studied historically and physically. The great basin of the Rhine is

also naturally divided into three grades—the Swiss highlands, the German

moderate plateau, and the lowlands of Holland. In a similar manner there

may almost always be traced in rivers three natural grades, and where

they do not have, as in the cases just cited they do have, a historical

significance, their physical influence is not hard to trace and to follow

into all its analogies.

The word water-shed, now a familiar one, is applied to that point

of division where contiguous springs pour their water in different

directions. It is not even in a mountainous country necessarily

coincident with the highest points of the chain, though it may be; the

valleys may slope in such a way as to have more influence in determining

the direction of running water than the mountains hard by. Every stream

has its own water-shed system, and this system is the real boundary of

its basin. If we trace this basin to its very limits on the highlands,

we may find, not a mile away, the beginnings of another river, which

shall flow in just the contrary direction, as for example in the case of

the Rhine and Rhone, the Volga and the Dwina. The sources of the Missouri

and of the Columbia lie close together, not a quarter of an hour’s walk

apart; yet the waters of one flow into the Atlantic, of the other into

the Pacific, and their mouths are almost 2500 miles apart. The Mongolians

hold the water-shed in such estimation that they throw up a heap of

stones wherever one occurs, establish it a shrine for prayer; and the

Toongooses of Siberia never pass by one without casting a cedar branch

upon the stone heap, that, to use their expression, “the holy mountain

that parts the waters may not lessen, but increase.”

The main channel is the stream proper; the others are tributaries. The

longest tributaries coming in from the region where the river proper

rises, can be grouped intimately with the source of the main current,

hardly distinguished from it in relative importance—the two, for

instance, in the Nile, the five in the Indus, two in the Ganges, three

in the Amazon, etc. All form in their confluence the real channel of the

river. And the entire body of tributaries, taken in conjunction with

the river proper, forms the river system, and the district which they

all drain is their true reciprocal. The two, in their mutual action and

reaction, form a whole, and are always thought of together. The source

and the mouth are the beginning and the end of the whole system; the main

channel and the circuit of water-shed, the center and the circumference

of it. All the tributaries in their union constitute what may be called

the arterial system of the river basin; the form of each and the

characteristics of each are analogous to those of the whole, only in

reduced pattern. The network which all the tributaries make is often

surprisingly intricate. The symmetry with which the main characteristics

of a river system are carried into the details, even of its smallest

accessories, can only be compared to that observable in the architectural

regularity of a tree, as it expands from the main trunk into the

countless symmetrical branches.

There are some rivers which are entirely independent of tributaries—which

pursue their way to the sea entirely alone. Such rivers, however, never

belong to the first class; they are always of subordinate magnitude,

and the humblest of them are mere coast torrents, like those west of

the Andes. Others find their way to no ocean, but lose themselves in an

inland sea or lake, as the Volga does in the Caspian; as the Gihon and

the Sihon do in the Aral; as the Jordan does in the Dead Sea. Others

disappear in sand wastes or in morasses; such are the rivers of the

African steppes. Others are blocked up, as it were, by the tidal wave of

the ocean, and are thus converted into estuary lakes.

There are some rivers, also, which remain equally or nearly equally full

the whole year through; there are others which have their seasons of

overflow: the Nile, for instance, and many rivers whose basin lies within

the region of tropical rains; there are temporary rivers, now full,

now empty, which, if they do not leave, like the torrents of Arabia, a

perfectly dry bed, are traced in the dry season by a row of stagnant

lakes, such, for example, as are found in the swampy lands of Australia.

Rivers more closely considered.

What is peculiar to every river is determined by the abundance of its

sources, the forking of its tributaries, the rate of its descent, the

distance from its most remote springs to its mouth, the main direction

of its course, and the greater or less sinuosities of its channel, as

occasioned by the structure of the country which it traverses.

The abundance of its waters is conditioned by the greater or less amount

of snow which finds the highest springs, the heavy rains which it

receives in tropical countries, and the exceedingly varied influences

which temperate climates may exert upon it. The fall softens from the

rush and plunge of the mountain district, first to an arrowy swiftness,

then to a moderate course, then to a beautiful gliding motion, to end

with an almost imperceptible flow just before entering the sea.

The direction of rivers is determined:—

1. By the structure of the region which they traverse, the layers being

in some places horizontal, and in others tilted to a vertical position;

here grouped, as in the granite Carpathian chain, in such a way that the

river courses which begin there run in parallel lines, radiating like

the rays of a star from a central point; then grouped in such a manner

that a stream may receive tributaries from two nearly contiguous ranges,

as among the spurs of the Ural Mountains, the Rhone in Valais, receiving

waters from the Bernese Alps at the north, and Pennine Alps at the south;

the Isère, in like manner, the Upper Rhine in Grisons, the whole Upper

Inn in Tyrol.

2. The direction is also determined by the mutual action of tributaries

and the main stream at the point of confluence. Very often the union of

two powerful currents gives rise to a third direction, according to the

law known as the parallelogram of the forces. This generally occurs when

no obstacle stands in the way of their taking a normal course, and is

exemplified in the cases of the Kama and Volga, the Theiss and Danube,

the Rhine and Main, the Saone and Rhone. Where an obstacle stands in the

way, their abnormal direction is manifested in the abrupt bendings of the

river bed. An instance is found in the bending of the Rhone northward

as it emerges from Valais. Its lower course, from Lake Geneva to Lyons,

betrays the same angularities, resulting from the obstacles which it

meets and cannot remove. The Rhine, breaking through the Jura at Basel,

is another instance; the Rhine, between Bingen and Caub, and the Dal-Elf,

in Sweden, also exemplify the same.

In case that rivers meet in their course large masses of stratified

rocks, they force their way through them in a zigzag direction, making

sharp angles always, and not unfrequently right angles, even. Instances

of this are found in the Rhine, between Mayence and Coblentz, and in the

Moselle, between Treves and Coblentz. When the river passes beyond these

rocky barriers, and meets with obstructions of a more movable character,

it crowds them more gently and gracefully aside, and leaves a path more

sinuous and wave-like; and yet more gentle are its curves, as it opens a

way through the plains where nothing obstructs its course. The last is

strikingly exemplified in the rivers of eastern Europe, especially in all

those of middle and southern Russia. The practised eye can determine the

structure of the soil with considerable certainty, by merely tracing the

course of rivers when represented on a faithful map. For, unless there

be other reasons to prevent, rivers always force their way where there

is the least resistance to overcome. In stratified rocks, where the tilt

is so great as to make the strata vertical, the river beds usually run

parallel with the lines of stratification. Instances are found among

the Alpine rocks, in Valais along the Rhone, in Tyrol along the Inn and

Adige, in Grisons, and among the Jura along the Rhine. Where the lines of

stratification are horizontal, rivers usually take their course through

the most marked ravines and fissures.

In most mountains, however, the lines of stratification are neither

vertical nor horizontal, but intermediate between them, more or less

sloping, as in most marked ranges of central Germany, for example. In

such cases, the process of excavating river beds has been determined by

various circumstances and conditions, and the direction of their channels

does not alone depend upon the extent and tilt of the strata, but also on

other forces which have exercised a favoring or a retarding influence on

their direct course. The stratification has its influence, indeed, but it

is general rather than specific. Still, it is very largely felt when it

happens to coincide in its main lines with the direction of the mountain

range, but is comparatively insignificant when it does not. We have

instances in the Alps where the axis of stratification coincides with

that of the main chain, from south-southwest to north-northeast; in the

Jura, from southwest to northeast; and in the Scandinavian range, from

south to north.

The different geological formations found in mountain districts have

a very important influence in determining the direction of rivers.

Mountains do not generally consist of rocks of one kind of structure,

but of several. What stratification is to mountains whose geological

formation is the same throughout, the superposition of different kinds

of rocks is to those of composite materials. The layers may be divided

into superior, inferior, and adjacent. These usually vary in respect to

age, and may be traced in a regular geological seniority, as for example

sandstone, gypsum, limestone, gray-wacke, and granite. These formations

are either closely contiguous, or are separated merely by valleys, as

for instance in the Carpathian chain, where the central granite knot is

separated by valley plains from the more southern limestone chain; an

example of contiguity is found on the west spur of the same Carpathian

range. Wherever mountain systems of varied geological structure approach

each other very closely, rivers seldom break their way through either

one, but find their way along the roots of the mountains, till at last

they come to a less confined place. Such river courses are often very

large and deep; for the mountain streams which meet and are hemmed in

by the narrow pass between the two contiguous ranges sweep all loose

obstructions before them, and not only leave their path clear, but

continually deepen it. We find this in the Ural, the Isère, the Rhone,

Aar, Inn, in all the long and winding Alpine valleys, and in the Ebro,

fed by the parallel ridges of the Pyrenees. The circle of rivers which

girds the central Carpathian knot is an illustration of what was said

a moment since. The Poprad, Dunayic, Arva, and Waag are found where

the true Carpathian chain, which is granitic, is closely contiguous to

subordinate ranges of limestone and gray-wacke. In any accurate map,

the long, winding course between these two chains may be easily traced.

Looking at the point where the Hartz Mountains and the Thuringian ridge

touch at their roots, the groups are seen to be insulated, as it were,

by the rivers which gird their bases. In the great streams of southern

and southwestern Asia, too, the line of the water-courses can be traced

along the narrow valleys which separate main from subordinate mountain

chains; the Terek, Kooban, Koor, Aras, Euphrates, Tigris, Indus, Ganges,

and probably the Chinese rivers, are all examples of this.

Some streams seem to be entirely independent of all these laws in forming

their channels, and to have their direction assigned to them by the

freaks of nature, such, for instance, as fissures in mountain chains and

clefts, which remain to indicate ancient convulsions.

The entire course of a river is divided into three distinct and

subordinate courses—the upper, middle, and lower. To these and their

respective tributaries correspond the three grades of transition found

on the banks, and which have already been alluded to. Not only the total

amount of fall in the river bed, but also the angle of inclination,

and the whole complex of phenomena in the basin, are reciprocal to

the threefold character of transition in almost every hydrographical

system in the world. Still, the variety of relations which arise from

the combination of different elements is so variable, that an almost

infinite diversity arises in the characteristics of rivers, and these

characteristics always vary, too, according as found in the upper,

middle, or lower course.

Upper Course of Rivers.

This begins at the ridge of the water-shed, and extends to the limits

where the river emerges from the most rocky highlands. It depends for

its existence upon the greater fall in the river bed there than lower

down. At the upper course, therefore, rivers which may flow in exactly

opposite directions are brought into direct neighborhood. The farther

they advance from the water-shed the more they recede from each other.

In the High Forest south of the Carpathian chain, and in the Bory Morass

north of it, the waters which flow into the Baltic and into the Black

Seas spring from the ground side by side. The name given to the districts

where the head-waters of large and navigable rivers part is usually the

French word portages, the English word transports being little used in

that connection, although all, the German Trageplatze and the Russian

Wolok, involve the idea of _carrying_, of porterage, from the head-waters

of one stream to those of another. The lowest parts of a water-shed, the

passes of a high mountain range, for example, the intermediate vales of

lower ones, and the most elevated plains in flat districts, are the most

suitable for the purpose of canal building, to serve as a connecting link

between the sources of divergent streams; as, for instance, the canal

which is proposed to connect the Baltic and the Black Seas by uniting

the Vistula and Danube, the tributaries, the Poprad, Hernad, and Theiss

being the channel of communication up to the mountains where a canal

is to pass over the water-shed formed by the valleys of the Carpathian

chain. Such a communication is the most available which can be made

between the opposite sides of a mountain range. The practicability of

constructing such canals depends very largely upon the degree of fall in

the upper course of the connected rivers, as determined by the slope of

the bed toward the horizon. The grade of most mountains’ sides, which

stand back to back, is unlike on the two sides: steep on the one, slight

on the other. Upon this depends the greater or less wildness of the

streams flowing through their upper course. In the Ural chain the slope

is steep on the eastern side, gradual on the western; in the Caucasus,

steep on the north, gradual on the south; in the Carpathian and the

Alps, just the reverse—steep on the south, gradual on the north. The rate

of fall varies; but, in general, it lies between an angle of 2° and an

angle of 6°, taking the entire upper course into account. On the very

steep north side of the Pyrenees, the fall is between 3° and 4°; on the

south side of the Alps, from the summits of Mont Rosa and Mont Blanc to

the plains of Piedmont, it is 3¾°. It is far less in more unimportant

ranges. And this angle, it should be remarked, is an average; it is the

resultant of a great number of special, short slopes, which vary from the

perpendicularity of an occasional waterfall to the equally occasional

tranquillity of a meadow-like flow. The incidental slopes are, of course,

much greater than the average of all. A grade of 15° is very steep; it

is the maximum that can be ascended by a beast of burden. A grade of

8° is the maximum for wheeled vehicles; all roads must be less sloping

than this. To accomplish the ascent of 35°, a man on foot must have some

assistance. A grade of 44° in the high peaks of Mexico and Peru, Humboldt

found inaccessible; only where the growth of trees and shrubs gave him an

opportunity of planting his feet, could he climb where it was a little

steeper than 44°. The Carpathians and the Pyrenees, on account of their

steepness and their scanty verdure, are very difficult to ascend. The

Alps are much more easily climbed than the mountains just mentioned, in

consequence of their abundant growth of turf and undergrowth. The richest

Alpine meadows of Switzerland have an inclination not exceeding 20°; at a

greater slope the vegetation becomes more sparse. The grade on which it

is possible for earth to cling, Lehman fixes at 45°, and considers that

the normal slope, because at a greater angle, rain glances or ricochets.

But Lehman is not right in assigning this as the normal slope possible

for earth to cling and vegetation to grow, for on the Alps soil adheres

and plants get a footing at a much steeper angle than 45°; in fact, the

modifications in the appearance of the Alps, by the growth of trees

clinging to steeper slopes than this, are very marked. From the highest

possible grade where vegetation can get a footing, we advance to the

sheer perpendicular.

The upper course of rivers is characterized rather by plunges than by

equable flowing, and determines its way by a series of leaps through

zigzag cuts and various ravines. It traverses bowl-shaped hollows and

narrow defiles, and makes its way even through mountain lakes, depositing

in them its residuum of sand and gravel which it has caught up and swept

along. In its wild plunges it draws into its body considerable air, which

appears as bubbles, and makes it a white mass of foam. By-and-by it

reaches more level ground, becomes clear as crystal, and assumes a rich

emerald green, or a deep blue. It is unnavigable, wild, romantic, and is

always found in mountain districts.

The brawling brooks of Salzburg, of the Pyrenees, and of Sweden and

Norway, all partake of this character. Those of the Pyrenees have a fall

of an inch in every foot, and in some places cataracts of two or three

feet. The same is observable in the Alps, where the continual stir of the

water mixes in air enough to turn all into a mass of silvery-white foam.

The Carpathian waters are the same before they reach the high plateaus

lying at their feet. The Alpine lakes, too, which lie within the upper

course of the rivers which feed them, have a considerable fall; Lago

Maggiore, for instance, has a descent of 52 feet between Magadino and

Arona.

In all the most marked mountain systems of Europe, the upper course of

the rivers is especially prominent. Northern Europe is characterized by

the fact that its streams have, throughout the most of their length, the

peculiarities of the upper course—whether observed in northern Russia, in

all Sweden, Norway, and Scotland.

With the exit of the river from the mountain district, all these

relations are changed, and a new character begins.

The Middle Course.

Far more moderate is the descent after the river emerges from the

mountain region, or where it has never experienced the wild turbulence of

the upper course, as is the case in most of the rivers of eastern Europe.

In the middle course the angle of inclination is much modified. The upper

Main has a fall of 342 feet within three miles after leaving Fichtel

Mountains. The descent of most of the rivers of central Germany is much

less than this. The Neckar, whose sources lie 2084 feet above the sea, in

passing to Heilbronn, which is 450 feet above the sea, falls at the rate

of about an inch to every 32 feet. The fall of the Saale, after leaving

the Fichtel range, is about 20 feet to the mile; that of Naab, about 14;

that of the Eger, less; and that of the upper Oder, in Silesia, still

less. More gradual yet is the slope of the Volga bed, which falls but

1400 in about 2050 miles, considerably less than a foot to a mile; and in

its lower course its inclination must be still less.

The effects of the current must necessarily be very different from those

observable under the influence of the dashing and wayward upper course.

The name River Bed is given to the entire breadth of the hollow which

holds the river, and which varies in width according to the stage of the

water, especially in large streams like the great rivers of America. The

Mississippi is a mile wide at Natchez at low water, at high water almost

thirty. The Orinoco, at St. Thomas, is three miles wide at low water, at

high water it is over seventy. In the Volga and the Danube the stage of

water makes great differences in the width of the river bed. In summer

the depth and breadth are, as a rule, less than in winter.

The Channel differs from the river bed; it is the part of the river bed

which gives life and motion to the whole current. In the upper course the

channel and the river bed generally coincide; in the middle and lower

courses, on the contrary, the channel occupies but a very small share

of the whole bed, but yet it determines the direction, amount of fall,

and the rapidity of the stream. It lies usually not in the middle of the

river bed, but on one side; it passes, however, from bank to bank; it

is indicated by the movement of ships, which always follow it, and it

lies uniformly adjacent to the boldest shore. It widens the whole river

bed toward one side, and not toward both; and so streams which traverse

great plains, like the great Hungarian one, for instance, do not now run

through the middle, but course along at the base of the marginal bluffs.

In all such cases, it will be found that the channel hugs the boldest

side of the bed. All the four Carpathian rivers, as they wind out between

the main range and the subordinate ranges, have their steepest shore, not

on the side of the loftiest, but on the side of the boldest mountains,

and these are the ones of the subordinate range. So, in the plains which

lie between the Swiss Alps and the Jura, the bold sides of the river bed

lie on the side of the bolder though less important chain, and not on the

side of the Alpine meadows. The bold banks of the Ebro are not on the

side of the Pyrenees and their plains, but on the south side. All the

streams of South and Middle Russia have, therefore, on the east side,

their low banks, on the west the bold ones; and this, because the most

extensive plains lie on the eastern side.

In the more level tracts the windings of rivers are very much increased

in magnitude. These windings check the current. The serpentine course

is characteristic of rivers in their middle course, and it is repeated,

though on a small scale, in every meadow brook. The serpentine course of

rivers gives rise to countless islands and intervals: as, for example,

between Bâle and the Rhinegau, but, with very few exceptions, no lakes,

the characteristic feature of the upper course of rivers. But the broad

meadow lands of the middle course very often indicate in the clearest

manner that they were once lakes of considerable magnitude, which have

subsided and left their basin a dry plain. An example may be found in the

meadow land of the Rhine, from Bâle to Bastberg, below Strasbourg, and

again from Ladenburg, in the Palatinate, to Bingen. So on the Danube,

from Ulm to Passau, Lintz, and Kloster Newburg, and again from Pesth

to Beloro Semlin, as far, in fact, as the narrows at Orsova. The same

feature is met in the middle course of the Volga, from Tver eastward to

the west Ural, and southward to Saratov and Kamishin, where it breaks

through the Obstshei-Syrtis, which was, doubtless, once the barrier of

a great inland lake. In these basins, now dry, there is a surprising

uniformity of characteristics wherever on the globe they occur. They

differ but little, whether found in the middle course of the Ganges,

the Indus, the Euphrates, or the American rivers. The still, incomplete

stream of the St. Lawrence shows us, even in the present, what the

ancient conditions were before they solved the problem of their complete

development. There, a row of such lakes as formerly existed in the now

fruitful plains of the middle Rhine, the middle Danube, and central

Russia, are the five great Canadian lakes. They still constitute the

middle course of the river, and one pours itself directly into another,

either over a gentle slope of land, or in a great cataract and rapids,

such as we do not observe in the middle course of other streams, which

are not, like the St. Lawrence, incomplete. Only when waterfalls

disappear can the inclination of rivers become a gradual one. The

uniformity of the grade of their channel is, therefore, a sign that they

have attained to a complete development. In such, slight rapids remain,

instead of the ancient cataracts. The existence of those primeval falls

we find in all rivers, even in the Rhine and Danube. The rounded faces

of the rocks which once were the barriers to the rivers’ course, and the

debris once swept down from the mountains and deposited over the bottom

of the ancient lakes, show this.

The strongest instance of cataracts, resembling the ancient ones which

connected the lakes of nearly all the great rivers of the globe, is seen

in the fall of Niagara. That cataract is an epitome of the falls of all

other streams. The Niagara River conducts the water of Lake Erie, by a

channel 33 miles long, to Lake Ontario, 300 feet below it. At the Great

Fall the river plunges about 150 feet into a chasm which it has hollowed

out from the soft stone between the two lakes. The cataract was formerly

seven miles below its present location, and has been observed to be

steadily working backward since its discovery. In the distant future it

will, doubtless, wholly disappear, as all others have done. For the

Niagara is merely a striking instance of a principle once universal, but

which merely worked itself out on a smaller scale. The more fragments of

rock and mountain debris were swept along, the sooner were the primitive

falls rent away by the wash and the percussion, and the development of

the middle course completed.

The places of transition which lie between the higher dry basins and

the lower ones are still to be traced in almost all rivers; not by

great waterfalls, which belong only to the upper course, but by simple

rapids. They are more or less characterized by narrows, with steep, rocky

banks, where, doubtless, cataracts existed in the primitive times. They

are recognizable by this feature, that they are uniformly alike, and

distribute their force equally on both sides of the river. Examples may

be found on both sides of the Rhine, in the narrows between Bingen and

Bacharach; on the Elbe, from Tetshen to Shandau, Dresden, and Meissen.

In these places the rivers have a very tortuous course, and there are

whirls and rapids (rapides, sauts, of the French; saltos, randales, of

the Spanish; schewerin of the Russians) which impede navigation. In these

localities the entire aspect of nature is changed, and the landscape

becomes exceedingly beautiful. Here we find ancient narrow roadways;

here are places of great historic interest, and of great interest to the

naturalist, assuredly not of accidental origin, but in close connection

with the development of the river bed, and in close analogy with all

places of transition from highland to lowland.

We may, perhaps, mark these features in all the rivers of the earth.

A knowledge of them is essential to understand thoroughly the natural

development of a river system in its true parts; unfortunately, they

have as yet been too little observed and described. Among European rivers

they are found in the Guadiana, at the Saltos de Lobo; in the Douro,

at the rapids below Torre de Moncorvo; in the Ebro, at Sastago, below

Saragossa; in the Rhone, the rapids below Lyons, between the granite

banks of Pierre Encise; in Loire, by Iguerando, below Roanne; in the

Rhine, below Strasbourg, and at the narrows at Bingen, near St. Goar and

Andernach; in the Weser, at the Porta Westphalica; in the Danube, at

Grein, at Kloster Newburg, and at Yachtali, Drenir Kapi, (Iron Gate,) and

Orsova; and in the Dnieper, the thirteen waterfalls below Yekaterinslav.

The same features are repeated in all the other streams of Europe and

the remaining continents. More close investigation of them will lead to

important results, concerning the structure of the earth in the regions

intermediate between plateaus and lowlands.

As a high grade, great cataracts, sharp and bold cliffs, and mountain

lakes characterize the upper course of streams, so rapids, dry lake

basins, and a meandering channel characterize their middle course. Below

the lowest rapids are found the level plains or lowlands which give

rivers their third characteristic.

Lower Course.

As soon as the rivers break through the lowest range of hills which once

beset their course, they deposit the debris which they bear with them,

and begin the formation of diluvial plains. We find in the soil of all

level places along the middle, as well as the lower course of rivers,

traces of the same kinds of rock and minerals, which characterize the

mountains where they rise. The rate of fall in the lower course of rivers

is so slight as to be almost imperceptible. Relatively, it is the

greatest in the Volga; from Kamishin to the Caspian the descent is more

than 150 feet, although the distance is less than 500 miles. The Senegal,

from Podor to the sea, a distance of about 200 miles, falls only about 2½

feet; the Amazon, within about the same distance, falls only 10½ feet, or

about an inch to the mile. In such rivers, therefore, the tide can flow a

very long way inland.

This gives rise to a great conflict of forces—the pressure of the stream

in its natural flow, heightened at the appropriate season by the annual

inundation, and the backward pressure of the tidal wave. Before these

forces come into equilibrium, the river bed is constantly changing. The

river proper seeks this equilibrium by a parting of its channel, dividing

into two mouths, as in the Nile, or into more than one, as in the Rhine

and Danube, or several (about 65) in the Volga. The momentum of the

stream, the resistance of the tide, and the consequent slow speed of the

current promote the fall of deposits along the lower course of rivers.

Below the surface the result of these deposits is found in sand banks

or bars; above the surface, as low, marshy land, the deltas, subject to

frequent inundation. We see this in the Rhine, the Nile, the Euphrates,

the Indus, the Ganges, the Mississippi—in all, about fourteen of the

first-class rivers of the globe. The contrary feature, single, broad

mouths not yet filled up by alluvial deposits, negative deltas, or deep

ocean inlets, can be observed in nine others of the largest rivers—the

Obi, Yenisei, St. Lawrence, Columbia, La Plata—mostly found, however, in

the north of the earth, where there is very little of the more loose and

fruitful soil which more southern rivers bear onward from the mountains

where they rise.

Another peculiarity of the lower course is seen in the extraordinary

changes in the river bed—the shifting of the channel from one side to the

other. This is the natural result of the very light and movable character

of the deposits brought down from above, and the strong pressure of the

current, which, though slow, has great momentum. In the lower course

of the Ganges, Indus, Euphrates, Nile, Rhine, and Po, these changes

can be traced as a matter of history, and, in the lapse of centuries,

have had great influence on the formation of the great plains of those

rivers’ mouths and on the people living there. With the lower course

begins the regular yearly inundations, which cover vast districts in

tropical countries; and to these inundations may be attributed the

gradual raising of the level of the plains covered by them. Hence arose

Herodotus’ descriptive phrase ποταμοὶ ἐργατιχοί, (prolific rivers.) The

great fruitfulness of these lowlands is well known. The rich alluvial

deposits have made Bengal, Babylonia, Egypt, Lombardy, Holland, and the

Netherlands the granaries of all neighboring countries.

In proportion as the mouth of great rivers resembles an inland sea,

having a strongly marked tidal flow in sympathy with the ocean, does the

whole nature of the lower course vary. The rivers whose mouths are turned

to the east and south are those which are exposed to the strongest and

the highest ocean waves. Such are Chinese, Indian, and South American

rivers, which sometimes show the result of this, 500 miles inland. The

tide extending so far into the interior facilitates navigation very much,

and transforms the lowlands along their margin into districts, which seem

transitional between true continent and oceanic islands. All the mouths

of first-class rivers which open toward the north and west are less

deeply affected by the entrance of the sea waves. To these belong most

of the European streams. Exceptional to both of these classes are the

three rivers, the Nile, Danube, and Volga, whose direction is not toward

the ocean, but toward the center of the Old World. They form a triad,

not of oceanic, but of continental streams; in them there is no ebb and

flood. Their lower course and mouths must, therefore, display different

relations from those of any other of the great rivers of the globe.

It was early remarked that not all streams, when they reach the sea, flow

at once into it, but come to a standstill. It is so with the Thames, and

with most of the North American rivers. The ocean sometimes throws a

tidal wave twenty to thirty feet high up their channel, and dams their

flow. Rivers vary exceedingly in their relations to this high barrier.

The Chinese streams are sometimes raised forty feet by it above their

normal level. This gives rise to a salt oceanic river, so to speak. It

is the same with the Thames at London. At high tide the surface is salt,

while the water at the bottom is fresh. The struggle with the downward

current and the upward current is very often visible. It is so in the

Orinoco, the Ganges, in the Chinese rivers; most of all, in the St.

Lawrence.

In all the continents there are many small rivers and rivulets which

have no normal mouths; which lose themselves in the earth before they

reach the sea. Sometimes they pursue a subterranean course, and emerge

again, though usually with a changed name. Among the best-known of such

instances is the Perte du Rhone, below Geneva, where the river flows

for a little way directly beneath a spur of the Jura Mountains. In like

manner, the Meuse, which loses itself in the earth at Bazoilles, in the

Vosges Mountains, west of Nancy, flows in a subterranean bed as far as

Noncourt, nine miles distant, and then emerges. The phenomenon is common

among the Jura, and in the limestone cliffs which feed the Drave and

Save. The tourist meets almost hourly there some brook or little river

disappearing beneath the ground. On the high Asiatic plateau of Gobi,

68 rivers are known, which disappear in a similar manner; in the north

of Thibet there are 115 such. They are common, also, in the Chinese

province of Yun-nan, on the Persian highland, and on the plateau of the

Bechuanas, in South Africa. In South America, between the Andes and the

La Plata, there are twelve lakes without effluents, the greatest being

Lake Titicaca. In Central America, there is the Lake of Mexico.

The division of the whole length of a river into the three courses—the

upper, middle, and lower—and the proportionate share which each of these

bears to the whole, depends upon the height at which the source stands

above the mouth. The greater or less extent of the transition grades,

and the greater or less extent of navigable waters, also depend on the

same. The upper course has, as a general rule, too many hinderances to

be very valuable for navigation; it is, at best, adapted only to boats.

The more united and deeper middle course offers facilities for vessels of

considerable draught; yet the frequent sunken rocks and eddies and rapids

are a great impediment to navigation. We find it so in the Rhine, below

the Falls of Schaffhausen, as far as Bâle; and in its middle course, at

Bingen and St. Goar; in the Danube, also, at Grein and Orsova.

The lower course, on the other hand, opens like a broad fresh-water sea,

that sometimes allows large ships to sail 50, 200, and even 500 miles

inland. These maritime streams ought to be discriminated from others;

the Chinese call them “sons of the ocean.”

The proportions in the length of the upper, middle, and lower course of

rivers are exceedingly variable; and equally variable of course are the

transition lands apportioned to each, and forming its natural supplement.

The upper course of the Volga is very short, the middle very long,

and the lower very short. The same relative proportions, though with

very different dimensions, are found in the Vistula, the Ganges, the

Euphrates, and the Mississippi. The upper course of the Rhine, on the

contrary, is very long, through all Switzerland to Bâle; the middle also

very long, to Cologne; the lower, very short, to Rotterdam and the sea.

It is the same with the Nile, the Danube, and the Indus. In the Marañon

or Amazon the upper course is very short, the middle and lower very long.

In the Chinese rivers Hoang-ho and Yang-tse-Kiang all the three courses

are relatively long.

The length of the middle and lower courses, although important

conditions of navigation, are not the only ones. Others are not to be

overlooked,—the amount of water, depth of channel, and the like. These,

however, are not capable of being generalized under any law, but depend

upon the individual characteristics of each stream. Every river needs,

for an exhaustive account of its features, its own monograph.

There remains but one important point to be considered—one which has

exerted a very great influence on the diversity of structure in all river

systems, controlling the area of their drainage, their volume of water,

their effect on human culture, and on the ethnographic character of the

people dwelling on their banks. It is the distance from the source to

the mouth in direct distance compared with that following the tortuous

course of the stream. The two lines almost never coincide; they generally

lie far apart. And the less they approach to coincidence, the greater

becomes the area of the river basin; the more numerous and valuable the

tributaries to the main course, the greater the volume of the stream and

the more varied and extensive its influence.

One or two examples drawn from European rivers will more fully explain

this point, to which Buache has already called attention in his

“Parallèle des fleuves.”

The mouth of the Volga is 982 miles distant from the source, in an

air-line. The distance, including all the curves of the stream, is 2012

miles, the bendings adding 1028 miles to the direct course. By this

doubling of the shortest possible distance, the area drained by it is

swollen to the enormous size of 657,000 square miles. The direct course

lies in a diagonal direction from northwest to southeast; but the real

direction is a changing one. First, it flows a short distance from north

to south, then in its middle course it has a double direction; first

eastward, toward the Ural chain, then to the south, and lastly, in its

lower course, to the southeast. Through this varied course it receives

tributaries from very remote sources, and waters a country altogether

greater than would be possible if the Volga’s course were direct from the

source to the mouth. Its basin becomes so large as to embrace a fifth of

Europe, and the stream becomes one of the longest and most available for

navigation in the continent. The vastness of the volume of water and the

wandering course have both contributed to the value of the Volga lowlands.

The exact contrast to the Volga is found in the Dniester. In the Volga

there is a maximum of windings; in the Dniester there is a minimum. The

air-line distance of the mouth of the Dniester from the source is 408

miles; the distance, including all the bends, is 450 miles; the loss in

winding is, therefore, but about 42 miles. The theoretical course of the

Dniester, _i.e._ measured by an air-line, would coincide very nearly with

its actual course. There cannot be, therefore, any distant springs whose

waters flow into its channel; its basin is one of the most contracted in

the world in consequence of its directness; and a small belt, embracing

but 32,850 square miles, comprehends the entire district that it drains,

freed from all those tributaries which make the Volga basin so important.

The Dnieper, its eastern neighbor, is 630 miles in direct distance from

the source to the mouth, but 1000 with all its windings; leaving 370

miles as the extraneous shore, which adds to the value of the basin, and

contributes to the 219,000 square miles which it drains.

The same contrast is seen elsewhere, though not on so extended a scale.

It is to be found in the Vistula, Oder, Elbe, Weser, Rhine, and Danube.

These rivers give shape to the transition terraces between broad eastern

Europe and the more contracted western portions of the continent; their

dimensions are, therefore, on a less extensive scale than in the great

Russian streams. Still, the differences in them are worthy of notice.

In the Vistula, the direct distance from the source to the mouth is

329 miles, and the real distance is 611 miles; the windings comprise,

therefore, 280 miles, or about two-thirds of the air-line from extreme to

extreme. It becomes able to receive a large number of tributaries, and

its basin is enlarged to an area of 78,402 square miles, becoming one of

the best-watered and most fruitful on the globe.

In the Oder, the direct distance from the source to the mouth is about

the same as in the Vistula. But while the latter frequently changes its

course, running first northward, then eastward to the Sau, then northward

again to the Bug, then westward to the Drewenz, and lastly northward,

and so gains a very large basin of drainage, the former is unvarying in

its course from southeast to northwest; so that the direct line drawn

from extreme to extreme, as the bird flies, is nearly coincident with

the actual course of the river. The windings do not, at most, comprise

one-third of the whole length of the stream, and the basin drained by its

tributaries is at least a third less than that of the Vistula, and is

proportionately less valuable to the interests of the world.

In the Elbe the air-line length is 394 miles, greater therefore, than

that of the Vistula or the Oder; its length, including its windings,

is about the same as that of the Vistula. The area of its basin lies

therefore between the two, 61,320 square miles; it is more valuable,

therefore, than that of the Oder, and less valuable than that of the

Vistula.

Still less striking in this respect are the Weser and the Ems; but the

Rhine assumes a prominence, in relation to the value of its basin,

greater than even the Vistula. The direct distance from the source of

the Rhine to its mouth is 423 miles, the actual distance 705 miles; the

windings comprise, therefore, more than two-thirds of the entire length

of the stream. The number of tributaries is uncommonly large, the area

drained is increased about 9855 miles beyond that of the Vistula; and the

entire basin (88,257 square miles) is one which has been of the greatest

import in the history of all central Europe.

All the rivers and all the terrace lands of the globe exhibit the same

relation which we have been briefly indicating in a few European ones;

in some of the great rivers of the world they are to be traced on a scale

of grandeur of which in those which have been touched upon scarcely a

suggestion is given.

But not in this feature, added to what has been already said, do we

exhaust the fruitful subject of Rivers, and the terrace systems which

accompany them from their source to the sea. The diversity of phenomena

traceable in them had hid their unity from geographers, and prevented

their tracing general principles in so manifold details. The dry, linear

representations on most of our maps have blinded the eye to the living

and organic relations which river systems enter into, and through which

they exert a great influence. They must be examined singly; they must be

studied in their real character and individuality, and each must have its

own monograph, before we can fully know the value of river systems to the

world.

We have now to touch upon one or two points omitted, thus far, in our

discussion of the hydrography of the continents.

The stream is a unit; most streams have a single channel as the last

goal of their descent. Others may have double channels, which contend

with each other for the superiority. If they are double only for a part

of the whole length of the river, and in the upper or middle course

flow together, and form one main channel, they can be called twin

head-streams. We have an example in the Danube and Inn, which are equally

long and equally large. Other instances are the Rhone and the Saone, the

Volga and Kama, the Missouri and Mississippi, the Blue and White Nile,

the Ganga and Jumna. Others have triple head-streams; as, for example,

the Hither, Middle, and Farther Rhine; the Ucayale, Huallaga, and

Marañon, which combine in the middle course to form the Amazon. There

may be even five head-streams, as in the Indus. Often it is only through

the usage of speech, often through ancient and exploded errors, that the

name of one of the head-streams is given to the whole river.

If the double channels continue through the whole length of the river

system, they belong to a different category; they become true double

systems, and have a double influence on the development of the whole

range of terraces from source to base. From their meeting in a common

bay or gulf at the mouth, they may be called sister-streams; and, from

the territory which they inclose between them, the Mesopotamia, they

may be called Mesopotamic streams. Between such double streams some of

the greatest States of Asia lie. Universally known, on account of their

influence on Asiatic culture, are the Euphrates and Tigris uniting in the

Persian Gulf, Ganges and Brahmapootra uniting in the Bay of Bengal, Gihon

and Sihon in the Sea of Aral, Hoang-ho and Yang-tse-Kiang encompassing

the Central Flowery Country of the Chinese Empire, and meeting in a

common delta. These double streams are mostly met in Asia, and they have

exercised a great influence on the whole growth of oriental civilization.

In South America there is yet another and more complex form yet of river

system. The Amazon is connected with the Orinoco by means of the little

cross-river Cassiquiare. By this connection the middle course of both

rivers is made more available to navigation than it would otherwise have

been. Such cross-streams may be found, though on a smaller scale, in

other continents; in Africa, for example, between the Senegal and the Rio

Grande. There a network is made between the parallel rivers, but it is

available for navigation only in the wet seasons. In Central Africa there

seems to be a similar phenomenon between the eastern tributaries of Lake

Tchad and the western tributaries of the Bahr el Abiad or White Nile,

though this rests on the authority of the Arabs. In India there appears

to be a similar connection between the middle course of the Indus and the

Jumna, and so the Ganges, by the mediation of the Sarasvati or Histara

and the Gharghara. There may have been the same in Central China, between

the Hoang-ho and the Kiang, where the Imperial Canal now runs; and a

similar feature may be found in the Lithuanian marshes, connecting the

Vistula and Dnieper river systems, through the mediation of the Bug and

the Przypec. The skill of man has, in many places, accomplished the same

end by the construction of canals.

Although all rivers, in the course of their development, follow the

universal law which leads them from their source, however high, to

the sea, yet there is, even in their descent, scope for exceedingly

varied phenomena. It is not necessary that everywhere a strongly-marked

line of water-shed should exist, but often, as in all the more level

plateaus, there are broad, neutral plains which perform the function of

water-sheds, though possessing no decisive character. It is so through

a great part of Central Asia, in the low plains of Australia, probably

in a large part of Africa, and so markedly in America, that all lines of

water-shed wholly disappear, and the rivers flow confusedly together,

without any system, and in obedience to no law.

Some rivers come down the sides of high mountains in torrents, then

course around in a long, winding course, turning out for all obstacles,

and at last find the sea. Others are entirely unlike them. The Ganges

flows from the south side of the Himalaya Mountains, and courses along

their base, following the direction of the chain in a southeasterly

direction, till it reaches the Bay of Bengal. The Indus springs from the

north side of the Himalaya, flows northwest over the plateau of Little

Thibet as far as Iskardo, then breaks through the whole chain to pour

itself out upon the lowlands of India, the Punjaub, and Mooltan. Dashing

its way through the most formidable barriers, it is entirely unlike the

gentle Ganges, which pursues its tranquil course through the plains,

meeting no barrier in its entire length. The Indus, so long as it remains

north of the Himalaya, traverses a plateau 10,000 feet above the sea;

while the Ganges, even at Delhi, is but 1000 feet above the sea. Both

rivers, although represented in precisely the same way upon the maps,

have an entirely different physical character.

The same difference in structure occurs in the streams of other

continents, and even in those of Central Europe, though on a less

colossal scale. There are, therefore, classes of rivers, and they ought

to be just as sharply discriminated as the classes in botany and zoology.

Plateau streams, such as the Danube, as far as the Lower Austrian and

Hungarian plains, and the Saone, down to its confluence with the Rhone,

pass through high, uniform plains with little fall. They are genuine

mountain followers, springing from the verge of the chain and crossing

along its base, the Saone taking the west side of the Alps, as the Danube

does the northern, and the Po the southern.

The rivers which force their way through mountain ranges form a second

class. The Rhine, a free child of the Alps, from its source to the sea,

breaks through all the ranges up to the Jura; then it forces a path

through all the mountains of Central Germany, till it comes to its lower

course. It may, therefore, be classified with the Indus. It leaves

the Alps suddenly at Bâle, and opens a new and romantic way through

no insignificant obstacle, and is everywhere a conqueror. That is the

peculiarity of the Rhine.

Two streams of analogous nature, though less marked in their

characteristics, are the Elbe and the Weser. But these both rise, not

among the Alps, but amid the German mountains. They lack, therefore, the

exceedingly romantic character of Alpine rivers; but they do not lack in

picturesque scenery, and this they owe to the obstacles which they pass.

The Elbe has broken its way from the Bohemian ridge through the so-called

Saxon-Switzerland, as far as Meissen, and the Weser from the fissures of

the Werra and the Fulda to the Porta Westphalica. The Elbe and the Weser

make, with the Rhine, the triad of Central European rivers, which have

broken a pathway for themselves through mountains which impeded their

course.

A third class of rivers are those which encounter no obstacles, and flow

in a placid stream from the source to the mouth. They extend in Europe

from the Vistula to the Ems, including the Oder and excluding the Weser

and Elbe, and from the Rhine along the whole Atlantic coast of France,

embracing the Seine, Loire, Garonne, and the Adour—all of these having,

in greater or less degree, the same hydrographical character.

From these can be still further discriminated the subordinate coast

rivers.

To a fourth class belong all those tributary streams, of whatever size or

length, which agree in possessing no independent character, and do not

pour their waters into the sea through their own mouths.

The application of this system of classification can be applied to the

streams and their accompanying terrace lands in the other continents. But

these observations may suffice to indicate the general principles which

we would apply to the study of rivers, and leave to the student their

further application.

Review.

The great typical forms already considered, highland, plateau, mountain,

lowland, terrace, and river, which all claim so large a share of

attention in studying their physical characteristics, are no less worthy

of careful attention, in consequence of their influence on human culture.

Our account would not be complete without devoting a few pages to the

consideration of the manner in which nature and history have reacted on

each other.

The most elevated highlands, the loftiest plateaus, uniform in their

aspect, immense in their extent, isolated, without trees, having the

thin soil characteristic of steppes, and useful only for grazing, are

the home of the primitive nomadic races. Without forests and without

shelter, without valleys and without water-courses, with sandy and rocky

soil, covered with a scanty vegetation, they serve only to supply food

for the gregarious animals which follow man, and to furnish a home to

wandering tribes of herdsmen. Instances are found in Central Asia, in

Toorkistan and Persia, in Central Africa, including the Galla tribes and

the Abyssinians. So, too, among the high plateaus of America, the home

of the primitive Aztecs. From such places came the first movements of

emigration; from the high plateaus of Central Asia came the wandering

Persians, Huns, Mongolians, and Turks; and the same course of emigration

was witnessed among the negro tribes of Central Africa, proceeding from

the Galla tribes. The lower highlands, less colossal in size, of more

moderate height, and of more genial temperature, have at all times

reached a certain low stage of culture, after giving a home to the nomads

from the higher plateau; but have never developed that culture to any

considerable extent. We find examples of this in the high terraces of

Bootan, the Deccan, and Persia; in Africa, among the Atlas mountains;

in Abyssinia, in the ancient Greek Arcadia, in Castile, in Arvernia,

(Auvergne,) in Gallia, in Hesse, in the Eifel, and on the Valdai hills.

In the exceedingly complex, subdivided, and romantic mountain districts

of the globe, the races have attained, by virtue of the variety of their

resources and the energy of their stock, to the highest results of

civilization, and have manifested the most independent and progressive

spirit. In such regions, hunting, working in wood, the settled life

of shepherds, working in metals, agriculture on such terrace lands as

those of Nepaul, Cashmere, Palestine, the Lebanon, Apennine, and other

ranges, fruit culture, tilling vineyards, the cultivation of all kinds

of industry, as in Central Germany and in most regions of the temperate

zone, develop most thoroughly and speedily the culture of a people. In

such occupations men learn to lean more on each other, and grow into

that diversity of occupation and division of labor, which are the latest

results of civilization. The Zend, the Sanscrit, and the Persian nations

which people the fertile tracts at the base of the Himalaya Mountains,

from Maghada, Lahore, Nepaul, and Cashmere, as far as Persepolis and

Hamadan, Susa and Shiraz, the inhabitants of the hill country of

Palestine and Syria, those of the Tehama range of mountains in Arabia,

those in the moderately elevated meadows of Gondar, as well as those in

all the European Alpine lands, Switzerland, Tyrol, Styria, as well as the

inhabitants of the mountain region of Peru and Mexico, all attain to an

early and considerably advanced state of civilization. Other nations have

found in mountains asylums in time of danger—the Tsherkeses and Ossetes

among the Caucasus, for instance, the Basques among the Pyrenees, and the

Gorals among the Carpathians.

The lowlands, as soon as the water had left them enough to make them

habitable, have become, from the first, the abodes of a teeming

population; and there has been the same blending of races in the most

ancient as in the most recently settled, in China as in Texas, and, in

truth, all North America. Often these inroads of population have been a

source of injury, as has been the case in the northern Siberian plains,

where the Finnish tribes have made their homes, and in the waste of

Sahara, where the Barbary tribes, the Bedouins, the Tibboos, and the

Tuaricks have made their retreat.

On the fruitful terraces, along the middle course of rivers, the earliest

fixed habitations and ripened culture have been attained. Through the

traditional handing down of past results, and by the habits of peace,

their inhabitants have more thoroughly subjected nature and advanced

to a higher state of civilization than the dwellers in the interior,

away from the rivers. It has been the same, in a great measure, with

the lower course, as, for instance, in Egypt, Mesopotamia, China, and

Bengal; and in Europe, in Lombardy, Holland, and the Netherlands, where,

to the efforts to recover land from the sea, have been added fishing and

commerce. On such fruitful tracts as the mouths and middle courses of

rivers water, nations could find a permanent home, and pass quickly to

all liberal and refining arts and occupations. This is clear, from the

instances of the eminent monarchies of the East, Meroe, Thebes, Memphis,

Babylon, Nineveh, Bagdad, and Mosul. So, too, on the Indus and Ganges, in

the domains of Taxila, Maghada, Benares; and later in the great empire,

whose centers were Agra and Delhi. China has arrived at its highest

civilization in the fertile district between its two greatest rivers.

Greece and Rome are marked exceptions. Their progress they owe, not to

great river basins, but to their peninsular form in the middle of the

coast of a delightful sea, full of islands and surrounded by lands in

a greater or less advanced state of civilization. England’s peculiar

maritime position has given it its wonderful vantage-ground for progress

in all human culture.

In the east of Europe, the basins of rivers have exercised the same

influence, to a certain extent, that has been hinted at above; and

Moscow, Kiev, Cracow, and Warsaw remain the seats of a civilization

which, rude as it was, owed its existence to the physical conditions of

the great Sarmatian river systems. In western Europe, the less marked

features of the country have contributed to the peculiar historical

development of the continent. The rich deltas have become the granaries

for a large part of the population, allowing industry to flow into

other channels besides agriculture. The sea-faring habits of the people

along the coast have broken up and done away with what is special and

provincial, and have conferred a cosmopolitan manner of living upon the

entire population. It was the same with the Phenicians in ancient times,

with the Portuguese in the middle ages, as it has been with the English,

Spanish, and Dutch in modern days. Fishing, navigation, and trade have

become permanent necessities of civilization. In the heart of continental

Europe, the rivers have had a great influence on the progress of nations;

the North German streams have extended their effect from the abode of the

ancient Saxons along the Baltic as far as the home of the Salic Franks on

the Scheldt, Seine, and Loire; the Danube, with its complex and important

system of terraces and lowlands, has opened communication between South

Germany and Hungary, Wallachia, and the East. The Vistula, Oder, Elbe,

and Weser have connected the homes of the old Sclavic population with the

Scandinavian coasts and the land of the Angles and Saxons at the neck of

Denmark, to the equal advantage of both. The great terrace system of the

Rhine, embracing the Odenwald, Hardt, Spessart, Taunus, Hundsrück, Eifel,

and the Siebengebirg, has thrown into the most active industrial and

commercial relations the whole district which it waters. It opened a way

to the Romans in their conquering advances before it did to the tribes of

Helvetia, Gallia, Germania, or the Lowlands: it sundered those tribes,

and kept them from preying upon each other; but, in the advance of

civilization, it has become one of the strongest bands to knit together

the central countries of Europe.

The Danube, with its extensive terrace lands, faces the east, and has,

therefore, very different relations to European history from the Rhine.

It is a double-headed river, and one of its head-streams, the one which

bears the name of the river proper, extends almost to the Rhine basin;

while the other, the Jura, has its source in Grisons, and hard by the

head-waters of the Rhine. As the Danube connects the Caspian and Black

Sea basin with western Europe, and the largest part of the Asiatic

immigrations have followed its course, the Danube has become the great

avenue between Europe and Asia. Celts, Teutons, and Romans were mingled

even before Christ, in Noricum, Vindelecia, Bavaria, and Suabia. How many

tribes may have been crowded westward by these, is unknown to us. The

same fate has happened to the people who settled there before Christ,

and the inroads of the Huns, Goths, and other tribes of similar origin,

scattered the older inhabitants over all Central Germany. We know, too,

that Sclavic, Hungarian, and Turkish incursions followed, each one

dispossessing wholly or in part the one which preceded it.

All great rivers and river systems have had a similar influence on the

course of civilization. There is not a single type feature in the world

which has not contributed its part to the advance of the human race; no

one is without its place and its function.