Alexander von Humboldt.

The travels and researches of Alexander von Humboldt online

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Fvstems. ' ' ^ 1 ,

ing and valuable account of the general character and

relative features of the great plains and mountain systems
of the continent of Asia. In no portion of his researches
are the great value of his varied acquirements and ex-
tended observations more apparent. Not only does he
deduce from his investigations of these external features
Katural laws, of our planet, new illustrations of the laws which govern
its internal constitution, and produce those great com-
motions of which the vast mountain chains and conca-
vities are results, but he also shows the permanent
influence which they have exercised on the distribution
of planets and animals over the globe, on the repartition
of heat throughout the different seasons, and on many of
the meteorological changes which exercise so important
an influence on climate, and on animal and vegetable life.
Influence on Their very direction appears to have largely affected
tioii'' ™'^"' the earliest migrations of the human race, and no doubt
also guided the course pursued in the divergence of ani-
mal life of every degree from the original Asiatic centre
to which sacred history and modern science alike point
as the scene of creation.
Systematic In pursuing his investigations into the physical phe-

UumboidL nomena of the Asiatic continent. Baron Humboldt has
aimed at reducing these to their most simj)le elements.
lie has accordingly, in considering the plains and moun-
tain systems of Asia, regarded Europe as a part of it,
setting aside what are fully as much political as physical
lines of demarcation, he regards Europe as a peninsular
prolongation of Asia, which from the extent of the sur-
face over which the conjunction is prolonged, affords
abundant opportunity for the continuation of the same



ELEVATED PLATEAUS. 363

structural system throughout the whole. The same chapter
singularly monotonous aspect pervades the vast area "^^^
extending fi-om Westphalia to the banks of the Obi Great plains
and the Lena. The great plains are evidently the pri-
mitive structures upheaved by some prolonged but
uniform action extending over an extremely wide area.
Upon this the chains of mountains have been superin-
duced by subsequent upheavals, acting more irregularly
over a more limited surface. The direction of south-
west by north-east is, however, traceable alike in the
principal axes of these vast elevated plateaus, and in the
chains of mountains of later formation ; so that a con-
nexion appears thus traceable in the sources of these Sources of
successive upheavals, though productive of results so
very different. The influence of the geological features
resulting from these combined actions is very remarkable.
The effect of these elevated plateaus, with their systems
of mountain chains, is specially noticeable in relation to
climate, and consequently to the distribution of the
vegetable kingdom, to the nature of the animals located
on their surface, and no less so to the physical and men-
tal peculiarities of the large portion of the human race
settled within these districts.

Leaving this extremely interesting branch of the In- Relations of
quiry which relates to the distribution of life in all its nio'untain
various forms as exhibited in the animal and vegetable systems.
kingdoms and in man himself, the observant traveller
next proceeds to examine the relative connections of the
area of the plains, and the area of the chains of moun-
tains, and deduces from thence important conclusions in
relation to the centre of gravity of that portion of our
planet whicli is elevated above the present level of the
sea. This subject had already excited much interest in
the minds of various distinguished European scientific
men, well qualified to investigate such phenomena, but
possessed of very limited opportunities of comparison
and observant study, when contrasted with those which
Humboldt has commanded during his sojourn on the



364



AREAS OF ELEVATION.



CHAPTER continents both of America and Asia. Tlie results of
^^^"^- one branch of Humboldt's elaborate investif^ations are
summed up in the following comparative statement of
all the observed areas of the Old and New World : —



Mean
Leiglits.



North America,
South America,
All America,
Asia,
Europe,



Area in Square
Marine Leagues.

607,000

571,000

1,178,000

1,34G,000

304,000



Mean height of tlie centre
of grarity in English feet

750
1132

934
1152

672



Mean depth
of sea.



Cnncluslnns
ot Laplace.



Extent of

eiTor.



Laplace had drawn the conclusion from his more
limited opportunities of observation and comparison,
that the mean depth of the sea nearly corresponded
with the mean height of continents and islands above
its level. Following out a naturally assumed analogy,
he &ho concluded that there must be great cavities
in the sea, corresponding to the lofty mountains on
the surface of the earth ; though, at the same time,
he conceived that, owing to the constant depositions
of rivers, the denudations of currents, and the shift-
ing of sands, as well as the accumulation of the exu-
vial of marine animals, it seemed likely the original
extreme depth of such cavities would be considerably
decreased. It will be seen, however, that the investiga-
tions of IIuml)oldt have led to very different conclu-
sions. According to Laplace, the mean height of the
continental regions of our globe above the level of the
sea, should be found to be 3284 feet, whereas Humboldt
assigns satisfactory reasons for concluding that it cannot
greatly exceed 1020. Not only does this conclusion
show Laplace's results to have been considerably up-
wards of two-thirds in excess of the true phenomena of
relative elevation, but it still more remarkably disagrees
with his ideas as to the true arrangement and compara-
tive deptbs of tbe bed of the ocean. Numerous import-
ant observations have been made of late years by able



MOUNTAIN SYSTEMS. 365

practical seamen on the actual depths of tlie ocean ; and chapter
soundings have been made to a depth of 8540 feet ^^^'^^^-
without finding a bottom ; so that, so far from the ocean Soimdinga
being only a repetition, in an inverse ratio, on an infe- " ''ocean,
rior scale, of relative depressions corresponding to the
elevation on the earth's surface, it seems now probable
that the bed of the ocean exceeds in depth, by five or
six times, the elevation of the earth's heights.

Manj' of the most remarkable investigations pursued Abstruse
by Humboldt, as the results of his study of the pheno- yons.
mena noted by him during his residence on the Asiatic
continent, are of so complex and abstruse a nature, as to
render it extremely difficult to reduce them to a popular
form. The conclusions, however, are in all cases re-
markable, and frequently of great practical value. Re-
marking on the singularity and uniformity of arrange-
ment discoverable in the mountain systems of Asia, our
traveller points out their apparent natural subdivision in-
to four systems, all running from west to east, along the
greatest breadth of the surface of the land ; while these,
again, are crossed by other mountain chains having a
meridional direction. Aiming at the discovery of some General
clearly pronounced indications of general laws, Hum-
boldt arrives at the conclusion that, in a portion of the
Asiatic continent most effectively surveyed by him, a
predominance of auriferous and platiniferous deposits is
clearly demonstrable in the latter mountain chains, or
those having a meridional direction. In these, as in so
many others of his most important conclusions as to
general laws, Humboldt was greatly assisted by his pre-
vious observation of the same class of phenomena, exhi-
bited on so gigantic a scale in the New World. In the Phenomena

of the New
Andes, in the southern AUeghanies, and in the moun- world.

tains of Brazil, all his conclusions pointed to similar
results, and led to his adopting the opinion that this
remarkable law was demonstrable in regard to the auri-
ferous alluvions of the American continent. Hence the
great value of the conclusion, put forth in the " Re-



366



ATMOSPHERIC PRESSURE.



Training
of previous
labours.



Natural
uptitudi.



CH.\PTKR searches in Central Asia," as well as in the previous pre-
^ ^^ ^' ^' paratory work, the " Frat^inens Asiatiques."

Hurabohlt had already been trained by his previous
labours, not onlj'^ as an observer and a collector of facts,
but still more, as a detector of those general laws by
which the numerous detached indications of such are
united into a consistent and harmonious whole. We
must not, however, overlook the no less important ele-
ment of success in the great natural gifts by which he is
so peculiarly fitted to become the scientific observer and
explorer. Training, and opportunities of observation,
were indispensable to him ; but without the natural apti-
tude for his important self-imposed duties, no amount of
preparatory trainint;, or means of observing, could have
fitted him for those remarkable generalizations by which
lie detected the operation of laws that govern the tem-
perature of the earth, the variations in its external form
and internal construction ; the disposition of its mine-
ral wealth ; the distribution of its living occupants, both
of the animal and vegetable kingdoms ; and the temper-
ature of the atmosphere, which exercises so great an
influence on most of these phenomena.
CUmatoiopy- On the general subject of climatology and atmospheric
jressure, Humboldt has thus expressed himself in his
later work : — " As the most important fluctuations of
the pressure of the atmosphere, whether occurring with
horary or annual regularity, or accidentally, and then
often attended by violence and danger, are, like all the
other phenomena of the weather, mainly owing to the
heating force of the sun's rays, it has long been sug-
gested that the direction of the wind should be com-
pared with the height of the barometer, alternations of
temperature, and the increase and decrease of humidity.
Tables of atmospheric pressure during different winds,
termed barometric windroses, afford a deeper insight into
the connection of meteorological phenomena. Dove has,
with admirai^le sagacity, recognised, in the 'law of rota-
tion' in both hemispheres, which he himself established.



ATMOSPHERIC CURRENTS. 367

the cause of many important i)rocesses in the aerial chaffer
ocean. The difference of temperature between tlie equa- -^^^^^^
torial and polar regions en£;enders two opposite currents Effects of
in the upper strata of the atmosphere, and on the earth's '^™^®'^ "^"^
surface. Owing to the difference between the rotatory ve-
locity at the poles and at the equator, the polar current
is deflected eastward, and the equatorial current west-
ward. The great phenomena of atmospheric pressure,
the warming and cooling of the strata of air, the aqueous
deposits, and even, as Dove has correctly represented,
the formation and appearance of clouds, alike depend on Formation
the opposition of these two currents, on the place where
the upper one descends, and on the displacement of the
one by the other. Thus the figures of the clouds, which
form an animated part of the landscape, announce the
processes at work in the upper regions of the atmos-
phere, and, when the air is calm, the clouds will often
present, on a bright summer sky, the ' projected image'
of the radiating soil below.

Where this influence of radiation is modified by the Continent.^

1 ,. .^. J. , i.' J. 1 J • and oceanic

relative position ot large continental and oceanic sur- jnfluencea.
faces, as between the eastern shore of Africa and the
western part of the Indian peninsula, its effects are
manifested in the Indian monsoons, which change with
the periodic variations in the sun's declination, and
which were known to the Greek navigators under the
name of Bippalos. In the knowledge of the monsoons, Monsoons.
which undoubtedly dates back thousands of years
amongst the inhabitants of Hindostan and China, of
the eastern parts of the Arabian Gulf and of the west-
ern shores of the Malayan Sea, and in the still more
ancient and more general acquaintance with land and
sea winds, lies concealed, as it were, the germ of that
meteorological science, which is now making such rapid
progress."

Not the least remarkable of the indications afforded, Obsena-
in late years, of the peaceful, but sure triumphs of sci- *°""-
ence, is to be found in the great chain of observatories, —



308



MAGNETIC STATION'S.



CHAPTER
XXVI II.

Astrono-
mical obser-
vatories.



Magnetic
EUtious.



Anticipated
results.



r>istribution

of liCat.



the fortresses of science, — spread over so vast a portion
of the known world. No longer confining itself to the
European centre of civilization, observatories for watch-
ing the stars, and extending the established truths relat-
ing to the vast system of worlds that glitter in our mid-
night sky, have been established in Africa and America ;
while across the hemispheres, which includes an import-
ant portion of the old continents of Asia and Europe, a
long continuous chain of magnetic stations has been
formed, extending from Moscow to Pekin, across the
whole of Northern Asia. At these stations, also, com-
plete meteorological observatories are established, so that
it can hardly be doubted important truths must result
from these, in relation to the great laws of nature, of
which these phenomena are only the indices or results.
On this Humboldt obsei-ves in his Cosmos : — " The com-
parison of observations made at places lying so many
hundred miles apart, will decide, for instance, whether
the same east wind blows from the elevated desert of
Gobi to the interior of Russia, or whether the direction
of the aerial current first began in the middle of the
series of the stations, by the descent of the air from the
higher regions. By means of such observations we may
learn, in the strictest sense, whence the wind cometh.
If we only take the results on which we may depend
from those places, in which the observations on tho
direction of the winds have been continued more than
twenty years, we shall find, that in the middle latitudes
of the temperate zone, in both continents, the prevailing
aerial current has a west-south-west direction.

" Our insight into the distribution of Iieat in the atmos-
phere has been rendered more clear since the attempt
has l)een made to connect together by lines those places
where the mean annual summer and winter tempera-
tures have been ascertained by correct observations.
The system of isothermal, isotheral, and isochimenal
lines, wliich I finst brought into use in 1817, may, per-
haps, if it be gradually perfected by the united eftbrts



CLIMATOLOGY. 369

of investigators, serve as one of the main foundations of chapter
comparative climatology. Terrestrial magnetism did not ^-^^'l-
acquire a right to be regarded as a science, until partial
results vi^ere graphically connected in a system of lines
of equal declination, equal inclination^ and equal in-
tensity.'''

The subject of climatology involves an extensive and Climatology,
extremely interesting class of phenomena, with their
resulting laws, — trade winds, land and sea winds, ocean
currents, the changes of seasons, &c. It also includes the
investigation of the curious results flowing from the ex-
tremely differing rates of variation of land and sea. From
the last of these arises the important contrast between
insular and littoral climates. "This remarkable contrast Differences
has been fully developed by Leopold von Buch in all its
various phenomena, ))oth with respect to its influence on
vegetation and agriculture, on the transparency of the
atmosphere, the radiation of the soil, and the elevation
of the line of perpetual snow. In the interior of the
Asiatic continent, Tobolsk, Barnaul on the Oby, and
Irkutsk, have the same mean summer heat as Berlin,
Munster, and Cherbourg in Normandy; the thermome-
ter sometimes remaining for weeks together at 86° or 88°, Excessive
whilst the mean temperature is, during the coldest
month, as low as • — 0°'4 to — 4°. These continental
climates have, therefore, justly been termed excessive by
the great mathematician and physicist, Buffon ; and the
inhabitants who live in countries having such excessive
climates seem almost condemned, like the sad expur-
gated souls in Dante's ' Purgatorio,' to suffer alike the
torments of heat and cold.

" In no portion of the earth, neither in the Canary Is- Astrachan.
lands, in Spain, nor in the south of France, have I ever
seen more luxuriant fruit, especially grapes, than in
Astrachan, near the shores of the Caspian Sea (46^ 21'.)
Although the mean annual temperature is 48°, the mean
summer heat rises to 70°, as at Bordeaux, whilst not only
there, but also farther to the south, as at Kislar on the



370



VAKIATIOXS OF TEMPERATUKE.



Important
chanjrus of
temperature.



CHAPTF.n mouth of the Terek, (in the latitude of Avignon and
XXV IIL j{,iiiiiui) the thermometer sinks in the winter to — 13"
or — 22°."

No less remarkable are the important changes in
temperature, animal and vegetable life, &c., produced
by relative position, and deu;rees of elevation. To this,
nearly as much as to tlie comparative distances from the
equator and the pole, belong the great variations of tem-
perature, and tlie changes in the living beings scattered
through different portions of the same zone; so that
it still remains an unsolved question, whether vast
tracts in the interior of the African continent are arid
wastes, burnt up by equatorial fires, or elevated plateaus
clothed witli the rich herbages and occupied by the
abundant life of a temperate clime. The Nile, it is now
all but proved, rises in mountains covered with eternal
snows, and in the supposed torrid centre of the African
continent, very recent discoveries have brought to light
a vast inland lake, or sea, the source of internal commu-
nication, as well as of a more tempered clime. " The
same relations," says Humboldt, " which exist between
the equable littoral climate of the peninsula of Brittany,
and the lower winter and higher summer temperature of
the reinainder of the continent of France, are likewise
manifested, in some degree, between Europe and the great
continent of Asia, of which the former may be consi-
dered to constitute the western peninsula. Europe owes
its milder climate, in the first place, to its position with
respect to Africa, whose wide extent of tropical land is
favourable to the ascending current, while the equatorial
region to the south of Asia is almost wholly oceanic;
and next to its deeply articulated configuration, to the
vicinity of the ocean on its western shores ; and, lastly,
to the existence of an open sea, wliich bounds its northern
confines. Europe would, therefore, become cohler if
Africa were to be overflowed by the ocean; or if the
mythical Atlantis were to arise and connect Europe
with North America ; or if the- gulf stream were no



Climates of
Europe and
Alrica.



CHANGES OF TEMPKRATURE. 371

longer to diifuse the warminn; influence of its waters CHAPTEK
into the North Sea; or if, finally, anotlicr mass of solid ^^^^L
land should be upheaved by volcanic action, and inter-
posed between the Scandinavian peninsula and Spitz-
bergen. If we observe that in Europe the mean annual Chances of
temperature falls as we proceed, from west to east, under [JJ'sain'cf ""^
the same parallel of latitude, from the Atlantic shores of r'H/'i'^^i of
France through Germany, Poland, and Russia, towards
the Uralian mountains, the main cause of this pheno-
menon of increasing cold must be sought in the form of
the continent, (which becomes less indented, and wider,
and more compact, as we advance,) in the increasing
distance from seas, and in the diminished influence of
westerly winds. Beyond the Uralian mountains, these
winds are converted into cool land-winds, blowing over
extended tracts covered with ice and snow. The cold Temperature
of western Siberia is to be ascribed to these relations of
configuration and atmospheric currents, and not — as
Hippocrates and Trogus Pompeius, and even celebrated
travellers of the eighteenth centurj', conjectured — to the
great elevation of the soil above the level of the sea."

But it is impossible to reduce within limited space, Extent of
and in a popular form, all the remarkable indications of ^"^ ^^'^
natural phenomena and great general laws, brought by
the extensive researches, and singularly sagacious con-
clusions of the great traveller.

Humboldt treats, in another of the remarkable works Views of
which we owe to his pen, of the sublime phenomena of
creation, as illustrated by science. This has been de-
signated " Views of Nature," and in it, also, he describes
some of the most remarkable natural phenomena of the
Asiatic continent. In the chapter in which he treats of
steppes and deserts, he remarks — " On the mountainous
range of Central Asia, between the Gold or Altai Moun-
tain and the Kouen-lien, from the Chinese wall to the
further side of the Celestial Mountains, and towards the
Sea of Aral, over a space of several thousand miles, ex-
tend, if not the highest, certainly the largest steppes in



372



ASIATIC STEPPES.



CHAPTER
XXVIIL



Vepctation
of the
steppes.



Eemarkatle
lieiglit of
flowering
plants.



Iiiflu.-nce on
pupiilutiou.



the world, I myself enjoyed an opportunity, full thirty
years after my South American travels, of visiting that
portion of the steppes which is occupied by Kalmuck-
Kirghis tribes, and is situated between the Don, the
Volga, the Caspian Sea, and the Chinese Lake of Dsai-
san^^, and which consequently extends over an area of
nearly 2800 geographical miles. The vegetation of the
Asiatic steppes, which are sometimes hilly, and inter-
spersed with pine forests, is in its groupings far more
varied than that of the Llanos and the Pampas of Cara-
cas and Buenos Ayres. The more beautiful portions of
the plains, inhabited by Asiatic pastoral tribes, are
adorned with lowly slirubs of luxuriant white-blossomed
Rosacea;, Crown Imperials (Fritillarice), Cypripediee, and
Tulips. As the torrid zone is in general distinguished
bj' a tendency in the vegetable forms to become arbores-
cent, so we also find, that some of the Asiatic steppes of
the temperate zone are characterized by the remarkable
height to which flowering plants attain ; as, for instance.
Saussurese, and other Synanthereee ; all siliquose plants,
and particularly numerous species of Astragalus. On
crossing the trackless portions of the herb-covered steppes
in the low carriages of the Tartars, it is necessary to
stand upright in order to ascertain the direction to be
pursued through the copselike and closely-crowded
plants that bend under the wheels. Some of these
steppes are covered with grass; others with succulent,
evergreen, articulated alkaline plants; while many are
radiant with the effulgence of licben-like tufts of salt,
scattered irregularly over the clayey soil like newly-
fallen snow.

" These ^Mongolian and Tartar steppes, which are inter-
sected by numerous mountain chains, separate the an-
cient and long-civilized races of Thibet and Ilindostan
from the rude nations of Northei-n Asia. They have
also exerted a manifold influence on the changing des-
tinies of mankind. They have inclined the current of
population southward, impeded the intercourse of nations



KACES OF CENTRAL ASIA. 373

r ore than the Himalayas, or the Snowy IMountains of chapter
Sirinagur and Gorka, and placed permanent limits to the -^ ^^^^ ^
1 rogress of civilization and refinement in a northerly
direction.

" History cannot, however, resrard the plains of Central ^J-^'"''' 9^ •

1,1 <• ? Central Asi.^

Asia under the character of obstructive barriers alone.
Tliey have frequently proved tlie means of spreading
misery and devastation over the face of the earth. Some
of the pastoral tribes inhabiting this steppe, — the Mon-
gols, Getse, Alani, and Usiini, — have convulsed the
world. If in the course of earlier ages, the dawn of civi-
lization spread like the vivifying light of the sun from
east to west ; so, in subsequent ages and from the same
quarter, have barbarism and rudeness threatened to over-
cloud Europe. ,

" A tawny tribe of herdsmen of Tukiuish, i.e. Turkish The Turkish
origin, the Hiongnu, dwelt in tents of skins on the ele-



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