Physico-Geographical Features—Deficiency of
Information—Barometer—Colonel Williamson—Lieutenants
Gibbon, Herndon and Maury—Señor Moro—Popagayos—Influence
of the Andes—Climate—Rainy Season—Colonel Hughes
—Statistics—Population—Indians—Vegetation—Building
Materials—Woods—Geology.
The present chapter includes certain physico-geographical features
subsidiary to the duties of the engineer and explorer. The object of
this paper excludes all matter, not possessing practical value for this
purpose, and admits of little more than mere mention.
The previous chapters indicate a deficiency in information in regard to
the following routes:
1. Nicaragua—The practicability of a route between Monkey
Point and the Lake Nicaragua, or San Juan River.
2. Chiriqui—No information extant.
3. Panama route, and improvement of the harbors.
4. San Blas and Chepo—A better line may be practicable.
5. Caledonia Bay, or the Gulf of Urabà to the Gulf of San Miguel,
by way of the Savana or Lara Rivers.
6. Examination of the depression noticed by Gen. Michler.
7. The line proposed by Sr. Gorgoza.
The elevation of the passes upon these routes should be definitely
fixed. The instrument which must determine the question of
practicability is the Wye spirit-level. If the capacity of the harbors
are insufficient for the largest class of ships, or can not be made
available at a reasonable cost, further examination is unnecessary.
BAROMETER.
Notwithstanding the improved formulæ, and more careful method of
observation recommended by Lieut.-Col. Williamson, Corps Engineers,
the barometer is subject to peculiar and anomalous variations, along
the slopes of the Cordillera of the Isthmus and the Andes. Lieuts.
Gibbon and Herndon refer to this phenomenon. Lieut. Maury attributed
the effect to the damming or piling up of the trade-winds against the
mountains. A recent traveler in the valley of the Amazon, I. Orton,
observed the same phenomenon, but objects to Maury’s theory.
Sr. Moro makes the following observations: “If, under these
circumstances (prevalent winds), barometrical observations are made
simultaneously on both sides of the Sierra, on the side of the Gulf,
they will exhibit a lower elevation than the true one, the error being
greater as that station may happen to be lower down or more towards the
north; but if time should admit of waiting until the weather be equally
fine on both sides (which seldom happens), then the difference between
the levels of the barometrical columns is insensible.”
Ventosa is peculiarly windy, and Nicaragua is subject to the Popagayos,
a species of monsoon, upon the Pacific coast. But the more placid
climate of the Atrato is similarly affected. “It is known as an
established fact,” remarks Capt. Kennish, “that the clouds seldom
pass over the Cordillera toward the Pacific, but are attracted by the
mountains, and disgorge themselves on the Atlantic side; hence the
reason of the perpetual rain, thunder, and lightning in the Atrato
Valley, while on the Pacific coast there is scarcely any rain for eight
months of the year.”
This unequal meteorological condition affects the barometer, and
General Michler observed unaccountable discrepancies in the readings of
two barometers when he reached the Hingador. With this exception, the
results of this officer’s observation were as close an approximation to
the truth as can be expected in a reconnaissance, but it is impossible
to say what given observation may be affected by some unknown cause.
A comparison of hypsometric determinations with the same altitudes,
ascertained by the spirit-level, will furnish some important elements
for eliminating errors. But this operation doubles the labor of the
surveyor, and time and cost of his explorations.
The errors of the barometer have led to singular inferences, and the
errors of observers to many more. Humboldt, La Condamine, Boussingault,
give a decreasing pressure along the Andes; and Orton, taking this
statement for granted, asks, “Are the Andes sinking?” The evidence of
geological and historical periods is, that the Andes and sea coast are
rising. The exceptions to this rule are local, and perhaps only in
appearance.
These objections to the use of this instrument only apply to situations
where the spirit-level can not be used. To determine heights
inaccessible to any other instrument, or for simultaneous observation
of the meteorological condition of an extensive area of country, the
portability of the barometer render it invaluable.
The height of the barometric column, on the Pacific slope of the Andes,
according to Orton, is 29.930. He gives two values for the Atlantic
side, 29.997 and 29.932. Michler gives the Atlantic coast of the Atrato
29.874.
CLIMATE.
A well-defined rainy season prevails for the most part throughout
the Isthmus, and permits the selection of suitable weather for
the operations of the engineer. Rain varies with proximity to the
mountains, etc., but the interval from December to May may be regarded
as the dry season. The seasons are sometimes reversed, as in Costa
Rica. There the dry season prevails upon the Pacific coast from
November to April, but on the Atlantic the contrary prevails. Fall of
rain in Honduras from May to October is 90.89 inches.
The tierras templadas, or elevated table-lands, are universally
healthy, and the climate in those regions possesses a charm which
belongs exclusively to the tropics. The unhealthy influences of the
marshes and sea-coast is much exaggerated, and may be said to cease
during the winter or dry season.
Col. Hughes, who visited the most insalubrious part of the Isthmus,
remarks that travelers, “who live like civilized beings,” have little
to fear from the climate. The writer spent six months, chiefly near the
sea-coast of Columbia, during part of the time compelled to sleep among
the swamps of the delta of the Magdelina, and although exposed to the
sun during the day, and sleeping in the open air at night, not one case
of febrile sickness occurred in the party of which he was a member, nor
were more than two cases of fever observed among the natives during the
period of residence.
The temperature varies with the elevation above the sea. Thermometric
records are of small value without the monthly and daily means of
localities.
The following table may give some general notion of their range:
════════════════════════════════════════════════════════════════════
_Fahrenheit._
─────────────┬──────────┬─────────┬───────┬─────┬──────────┬────────
│ TEHUAN- │HONDURAS.│BELIZE.│COSTA│NICARAGUA.│ATRATO.
│ TEPEC. │ │ │RICA.│ │
─────────────┼──────────┼─────────┼───────┼─────┼──────────┼────────
May │ 90° │ 71° │ 71° │ 57° │ 71° │Average
June │ 88° │ │ │ │ │during
April │ 83° │ to │ to │ to │ to │February
May │ 88° │ 89° │ 84° │ 85° │ 90° │ 75.2
June │ 81° │ │ │ │ │
December and │ │ │ │ │ │
January │ 74° │ │ │ │ │
─────────────┴──────────┴─────────┴───────┴─────┴──────────┴────────
In Guatemala average maximum 88.7°. Minimum 38.9°.
Statistics, governmental and social, of Central America, are very
uncertain. The revolutionary condition of a society, in which it is
the interest of the chiefs to impose unjust burdens on the people,
and of the people to deceive; where, before an enumeration can
fairly begin, the government which authorized it may be deposed, and
another substituted in its place; the poverty, anarchy, and social
demoralization which result, are circumstances very unfavorable to a
correct determination of the resources of the country, or the number of
its population.
The following figures may not be free from this uncertainty, but give
the best approximation that could be obtained:
_Population of the States of Central America._
═════════════════════════╤═══════════════╤════════════
│ SQUARE MILES. │ POPULATION.
─────────────────────────┼───────────────┼────────────
Tehuantepec │ ... │ 61,000
Costa Rica │ 23,000 │ 150,000
Nicaragua │ 48,000 │ 290,000
San Salvador │ 9,600 │ 294,000
Guatemala │ 43,380 │ 907,500
Honduras │ 42,000 │ 350,000
Panama, including Darien │ ... │ 168,000
│ ├────────────
│ │ 2,220,500
─────────────────────────┴───────────────┴────────────
This population is of a mixed character, composed of Europeans,
Mestizoes, Indians, Negroes, and Zambos; the European element being
largely in the minority.
INDIANS.
Explorers in every part of the Isthmus, with the exception of Darien,
give favorable accounts of the temper of the natives. Trautwine, who
crossed the divide at several points in the province of Chócó, regarded
a bundle of cigars as the best passport. General Michler depended on
the natives for provisions during a part of his survey, and was never
disappointed.
But the Darien and San Blas Indians have been permitted to threaten and
murder with impunity. They have been further emboldened by the timid
behavior, and exasperated by the conduct of expeditionists. Had the
hostile demonstration of the savages against Codazzi and Gisborne, and
the massacre of four of Capt. Prevost’s men, been promptly punished,
subsequent exploring parties might now pass through the country
unmolested.
Strain, who thoroughly distrusted them, acknowledges that in one case
his suspicions were unjust. After dismissing his guides, he remarks
that he “was afterward convinced that the Caledonia Indians, and their
Sucubti friends, intended to lead them by the most direct route to the
Savana, and that they were prevented doing so by the Indians of the
Chuquanaque, or the Chuqunos, whom they met on the seventh day’s march,
and whom from the first excited suspicion.” It would appear that this
unfortunate expedition would have been better served by a little more
confidence in these “formidable Indians,” as Gisborne calls them, and
a little acquaintance with their language, than by the fortitude it
afterward exhibited in encountering the trials which befell it.
When misfortune appeals so strongly to sympathy, as it does in this
case, criticism becomes an ungracious task. Throughout this paper we
have omitted much in observing the rule, laid down for ourselves, to
indicate what should be done, rather than notice what should not have
been done. We therefore quote with pleasure the following graphic
account of the difficulty of cutting a way through the tropical
undergrowth, which we find in Mr. Gisborne’s narrative:
_Cutting the way_, “we were wading along the river margin, or facing
clusters of prickly stems sometimes backing this mass of vegetation.
Every step had its difficulty, and every difficulty was attended with
additional bodily suffering; but our hearts nearly failed when an
interminable mangrove wood extended as far as the eye can reach.
“The twisted and interlaced roots, some eight feet high, grew out
of a bed of slimy mud, left by the tidal waters, making progress a
succession of gymnastic feats, in which the gift of balancing had no
small share. Hand and foot were equally occupied, and every muscle was
called into play; nearly an hour’s perseverance had only advanced us a
few hundred yards.”
Another description of the same character will exhibit some of the
difficulties: “Occasionally a swamp, growing an impenetrable mass of
vegetation, delayed our progress and expended our energies in fruitless
hacking. The only way to get through many of these cienegas was to
fall on one’s back into the middle of the matted vegetation, and then
compress a place the length of one’s self, which those behind trod
down. After persevering in this manner for several hundred yards, an
inlet would be reached with a soft, muddy bottom, and waist deep from
the flood. On the other bank, the same mode of progress had to be
adopted, until prickly palms, and still more prickly creepers, made a
variety in the difficulty and suffering.”
Strain met with similar obstruction. “Hitherto, Strain had led the
party, every day cutting a path with his cutlass. This was most
laborious, and Mr. Truxton insisted on going ahead in his place. The
undergrowth was exceedingly dense, and composed, for the most part, of
‘pinello,’ or little pine, a plant resembling that which produces the
pineapple, but with longer leaves, serrated with long spines, which
produce most painful wounds, especially as the last few days’ march had
stripped the trousers from many of the party.”
The best way to clear these obstructions has been found to employ
natives, with machetes. This method, invariably adopted in Central
America, has been recommended by Admiral Davis, who also advises the
explorer to carry with him a good supply of canned and concentrated
provisions.
BUILDING MATERIAL.
Suitable stone is found without difficulty. Hydraulic cement will
probably have to be imported, although hydraulic limestone is said to
have been found in the States of Vera Cruz and Oazaca.
The explorer will find difficulty in discovering building sand. The
sea beaches may afford suitable sand for hydraulic work. Bricks can be
manufactured, without difficulty, at many points.
WOOD AND TIMBER.
The following, from the account of Lloyd and Sidell, gives the local
names and character of the most useful species:
1. _Guachapali._—Abundant; four or five feet in diameter,
like walnut; good under water.
2. _Macano_, or _Cacique_.—Crooked, medium size;
good in ground or water; much used.
3. _Espino Amarillo._—Not abundant; good in water; yellow;
not liable to decay, or to be attacked by insects; straight;
easily worked; seven kinds.
4. _Cedro Espinoso._—Large, straight, light; heart alone good
in open air and under ground.
5. _Cedro Cerollo._—Large, crooked, durable.
6. _Cedro real, Amargo._—Finest cedar of the country; used
for many purposes in carpentry and boat-building; grows to
five or six feet in diameter, and is very common.
7. _Nispero._—Large; not easily worked; stands well when
sheltered; insects do not touch it; resists transverse
strain; two kinds much esteemed.
8. _Guayacan_, or _Guallacan_ (_Lignum vitæ_).—Common;
close-grained; heavy; works well when green; grows to four or
five feet in diameter; used for gun-carriages, wheels, etc.
9. _Algarobo._—Excellent wood; hard and tough; reddish brown,
with streaks; large; common; used for gun-carriages.
10. _Mangle Caballero_ (_Mangrove_).—Good as the Nispero;
abundant near water; gives pieces thirty to forty feet long, and
one foot square; used for vessels.
11. _Alcomorque_ (cork tree).—Supplies large beams, which
wear well.
12. _Malvicino._—Yellow; abundant; wears well; employed in
building.
13. _Caoba_ (mahogany).—Large; not heavy; good for interiors; if
not properly seasoned, is brittle.
14. _Robles._—Large; not heavy; easily worked; used for paddle
by the Indians; stand well in air; two varieties, one not good.
15. _Cocobolo Prieto._—Tough, hard; beautifully figured (like
rosewood); three feet in diameter; fragrant when green; used
for carpentry and cabinet work.
16. _Tutumia_ (calabash tree).
17. _Cano Blanco._—Cane; good for lathing when split.
18. _Quira._—Tough, close-grained, heavy; different colors,
from light brown to very dark; very high; from one to three and
one-half feet in diameter; plentiful; used in house-building.
19. _Madrono Fino._—Like box; one and one-half foot in diameter;
excellent wood for turning.
Mr. Loyd gives a list of ninety-five varieties of woods, of which list
the above are the most valuable.
GEOLOGY.
A mere enumeration of the geological specimens, which is all that
present knowledge upon this subject will permit, is not thought
desirable in this paper. Speculations and theories, if not premature,
would be out of place.
The physical geography of Central America is the proper subject for
a treatise. We have already seen how the table-lands of Guatemala,
from four to five thousand feet above the level of the sea, sink to an
insignificant height at Panama and Nicaragua. “There is no spot on the
globe,” says Humboldt, “so full of volcanoes as this part of America,
between 11° and 13° of latitude.”
Two or three volcanoes, Fuego and Agua, in the State of Guatemala, are
14,000 and 12,000 feet high. Some of the volcanoes of Nicaragua reach a
height of 7,000 feet. A common and remarkable characteristic of all of
them is, that they rise in a conical form from the plain.
_Gold and silver produce of Central America._
══════════════╤═════════════╤════════════╤═════════════
│ GOLD. │ SILVER. │ BOTH METALS.
──────────────┼─────────────┼────────────┼─────────────
1804 to 1848 │ $8,800,000 │ $4,400,000 │ $13,200,000
1848 to 1868 │ 5,000,000 │ 3,000,000 │ 8,000,000
├─────────────┼────────────┼─────────────
Total │ $13,800,000 │ $7,400,000 │ $21,200,000
──────────────┴─────────────┴────────────┴─────────────
The mines of the Provinces of Panama and the Veraguas are not worked so
extensively as they deserve to be. A small quantity of gold is annually
produced in the Republics of Nicaragua, Honduras, Costa Rica, and San
Salvador. The Costa Rican mint, in 1852, coined between fifty and one
hundred thousand dollars annually. The actual gold product is estimated
at ten times this amount. The most important mines in new Granada
(Colombia) are found in the State of Antioquia. In 1868, the yield was
$1,500,000 gold; $193,000 silver. The detritus of all the rivers of
this State is auriferous. An English company works the Marmato gold
mine and the Santa Anna silver mine, near Honda, on the Magdelina
River. They have provided twelve stamping mills, representing one
hundred and ten heads, which crush from ten to nineteen thousand tons
per year, yielding, on an average, eleven pennyweights eleven grains of
gold per ton.