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equally close-a decision of this long- quent revolutions of animal and vegetable inooted question which illustrates the life, induced by local position. It is on ancient axiom that truth is rarely found the mountain slopes of from three in extremes.

to seven thousand feet, beyond the One of the principal causes which

influence of the noxious miasmata, that modify the distribution of heat is ele

man dwells in perpetual summer amid the vation above the level of the sea.

aces

It

richest vegetable productions of nature. In is computed by meteorologists that the

the mountains of Jamaica, at the height of

four thousand, two hundred feet, the vegetemperature of the atmosphere sinks at the rate of 1o Fahr. for every hundred

tation of the tropics gives place to that of

temperate regions; and here, while thouyards of altitude above tide-water. paras 0 Anuae above Tae-water sands are cut off annually along the coast Consequently whenever land rises high by yellow fever, a complete exemption above the common level, a change of exists. In these elevated regions, the inclimate similar in its effects to increase habitants exhibit the ruddy glow of health of latitude, as regards the distribution which tinges the countenance in northern of temperature and the consequent dis- climes, forming a striking contrast to the tribution of plants, is induced. But pallid and sickly aspect of those that these effects differ greatly in different dwell below. In ascending a lofty mounlatitudes. Thus, under the equator, tain of the torrid zone, the greatest varieperpetual snow exists generally at ty in vegetation is displayed. At its foot. an altitude of fifteen or sixteen

on under the burning sun, ananas and planthousand feet, whilst in the 70th de

tains flourish; the region of limes and gree of north latitude, it is found at

oranges succeeds; then follow fields of

maize and luxuriant wheat; and still the height of three thousand three

higher, the series of plants known in the hundred feet. Receding from the equa

temperate zone. The mountains of temtor, these phenomena assume a more

perate regions exhibit perhaps less varieirregular character. The difference be- ty, but the change is equally striking. In tween the limits of perpetual snow on the ascent of the Alps, having once the northern and southern sides of the passed the vine-clad belt, we traverse in Himmaleh Mountains is not less than succession those of oaks, sweet chestnuts, four thousand feet; and whilst these and beeches, till we gain the region of the limits are at the equator nearly 3° more hardy pines and stunted birches. above, they are in the frigid zone more Beyond the elevation of six thousand feet, than 100 below, the freezing point. no tree appears. Immense tracts are In reference to the effects resulting

then covered with herbaceous vegetation, from the diminution of temperature

the variety in which ultimately dwindles attending the elevation of land, the

down to mosses and lichens, which strug. following observations are made by our

gle up to the barrier of eternal snow. In author:

the United States proper, we have at least two summits, the rocky pinnacles of which

shoot up to the altitude perhaps of six « Whilst the flowers of spring are un- thousand five hundred feet. Of these, folding their petals on the plains of nor- Mount Washington, in New Hampshire, thern France, winter continues his icy is one. Encircling the base is a heavy reign upon the Alps and Pyrenees. By forest-then succeeds a belt of stunted this beneficent appointment of nature, the firs-next a growth of low bushes-and torrid zone presents many habitable cli- still further up only moss or lichens, or mates. On the great table-plain of Mexi- lastly a naked surface, the summits of co and Guatemala, a tropical is converted which are covered, during ten months of into a temperate clime. As the vernal the year, with snow. Of the snow-capt valley of Quito lies in the same latitude peaks of Oregon, we possess no precise as the destructive coasts of French Guia. knowledge.” na, so the interior of Africa may possess many localities gifted with the same ad

The causes upon which this diminvantages. In our own country, reference : has already been made to the marked con

ished temperature in the higher retrast between the Atlantic Plain and the gro

gions depends are-first, the perfect parallel mountain ridges: but it is in the permeability of the atmosphere to the geographical features of Columbia, in solar rays; and secondly, its increased South America, that we find most strik- capacity for caloric in proportion as it ingly displayed the physical phenomenon becomes more rare. As the solar rays of height producing the effect of latitude- radiate through the atmosphere almost a change of climate with all the conse without affecting its temperature, it

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follows that the temperature of its of Pui, at about the same elevation,
lower regions is derived more immedi- there are produced, according to Cap-
ately from the earth Although the tain Gerard, the most luxuriant crops
atmospheric stratum immediately in- of barley, wheat, and turnips, whilst a
cumbent on the surface of the earth, litle lower the ground is covered with
owing to this rarefaction, naturally vineyards, groves of apricots, and many
ascends, yet, as its capacity for caloric aromatic plants.
at the same time increases, it loses ra- In considering the laws relative to
pidly its sensible heat. Hence, as we the distribution of plants and animals
ascend into the atmosphere, its tem- over the globe, we find that they are
perature diminishes precisely in the chiefly regulated by the temperature of
ratio that its latent heat, that is, its ca- the atmosphere. The circumstance
pacity for caloric, as produced by rare- next in importance is the nature of
faction, increases. To explain the dimi- soil, which has resulted from the gra-
nution of temperature on the summits dual attrition of the solid materials
of high mountains, no longer there. composing the crust of the globe; but
fore presents any difficulties to natural as regards the very existence of all
philosophers. As the atmosphere is animals, at least of the land, and all ve-
rare and diaphanous, but a small por- getables, we find this stratum of com-
tion of the heat of the solar rays which minuled mineral substances and organic
traverse it, is retained, and as the remains absolutely indispensable.
more dense inferior strata, heated by It is in tropical countries alone, be-
the surface of the earth, expand, rise neath a vertical sun, that vegetation
up, and grow cold from the circum- displays its utmost glory and magnifi-
stance alone of their rarefaction, they cence. It is there, amidst eternal sum-
encounter these summits, and rob them mer, that we find groves ever verdant,
of their caloric, which passes into a la- blooming, and productive. Advancing
tent state.

to the north or south, we soon discover
It is only, however, when lands are forests, which, denuded of their leaves,
considerably and suddenly elevated, assume during half the year the ap-
and exposed to the action of the almos- pearance of death; and still approach-
phere laterally, that this rapid conduc- ing the poles, we meet vegetable life
tion of heat and rarefaction of the at- under a variety of stunted forms, which
mosphere can take place. When large are ultimately superseded by a few
tracis of country rise gradually, the coarse grasses and lichens.
decline of 10 of temperature for every “The influence of temperature on
three hundred feet of elevation, as de- the geography of plants," says Dr.
termined either by a balloon ascension Forry," is ably pointed out by M. de
or by scaling the sides of isolated and Candolle. In considering its relation
precipitous mountains, does not by any with the organic life of plants, it is
means take place. The region of our necessary to keep in view three ob-
great lakes, for example, notwithstand- jects: 1. The mean temperature of the
ing it is elevated 600-800 feet above year; 2. The extreme of temperature
the level of the sea, so far from caus- both in regard to heat and cold ; 3.
ing a diminution of annual tempera- The distribution of temperature among
ture, produces, in consequence no doubt the different months of the year. The
of the great accumulation of summer last is the most important; but in the
heat by the soil, an augmentation. A investigation of vegetable geography,
most striking illustration of an analo- it is requisite to estimate the simulta-
gous fact is offered by the ridges and neous influence of all physical causes
valleys of the great Himmaleh moun- soil, heat, light, and the state of the at-
tains of Southern Asia, where immense mosphere, as regards its humidity, se-
tracts, which theory would consign to renity, and variable pressure. Each
the dreariness of perpetual congela- plant has generally a particular climate
tion, are found richly clothed in vege- in which it thrives best, and beyond
tation and abounding in animal life. certain limits it ceases to exist. Hence,
At the village of Zonching, fourteen having seen the great variations of
thousand seven hundred feet above the summer and winter temperature on
level of the sea, in lat. 31° 36' N., Mr. the same isothermal line, the absurdity
Colebrook found flocks of sheep brows- of limiting a vegetable production to a
ing on verdant hills; and at the village certain latitude or mean annual tem-

VOL. XI.-N0. LIII.

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perature, is apparent. To say that the the date, palm, and sweet orange, vine, the olive, and the coffee-tree, re- grow in Louisiana only to latitude 300. quire, in order to be productive, annual That these plants would succeed, how. temperatures of 539.60, 60°.80, and ever, on the Pacific coast of our terri64° 40, is true only of the same system tory, on parallels corresponding to of climate. As the annual quantity of Europe, is an opinion that has for its heat which any point of the globe re- basis the fundamental truth, that the ceives, varies very little during a long laws of nature never vary. It has, in. series of years, the variable product of deed, been recently stated, on the auour harvests depends less on changes thority of travellers, that even as high as in the mean annual temperature, than the forty-fifth degree, the fig, citron, orin its distribution throughout the year, ange, lemon, pomegranate, and cotton Thus climates in regard to vegetable plant, flourish. This, in truth, is conproductions, are strongly characterized firmed by thermometrical observations by the variations which the tempera- made by Mr. Ball, of New York, at Fort ture of months and seasons experience." Vancouver, in latitude 45° 37', situated

Reference has already been made to on the Columbia River, about seventy the contrast in the climate of Western miles in a direct line from the Pacific Europe and Eastern America, the for. Ocean. During a year's observations, mer producing the olive and the orange the lowest point is 179 of Fahr., and in latitudes which with us are produce the whole number of days below the tive of ice and snow. Scarcely does a freezing point is only nine, all of which winter elapse that the Hudson river are noted in January. The seasons are is not frozen over even in the vicinity even less contrasted than at Pensacola of the city of New York ; whilst Phila- or New Orleans. The mean temperadelphia and even Baltimore, lying on ture of spring, summer, and autumn, the same parallels on which flourish in are about the same as at Fort Wolcott, Europe the olive and the orange, have R. I., whilst the winter resembles that their commerce often interrupted from of Fort Gibson, Arkansas. “Though the same cause. The Delaware, which the latitude is nearly that of Montreis in the latitude of Madrid and Na- al," he says, “ mowing and curing hay ples, is generally frozen over five or are unnecessary; for cattle graze on six weeks each winter. Even the Po- fresh growing grass through the wintomac becomes so much obstructed ter. ... Winters on the Columby ice, that all communication with bia River are remarkably mild, there the District of Columbia by this means, being no snow, and the river being oba is suspended for weeks. Further north, structed by ice but a few days during we find the mouth of the St. Lawrence the first part of January," Here the shut up by ice during five months of seasons, notwithstanding five degrees the year; and Hudson's Bay, notwith- farther north than the city of New standing it is in the same latitude as York, are so mild and uniform, that the the Baltic Sea, and of thrice the ex- difference between the mean temperatent, is so much obstructed by ice, even ture of winter and summer is only in the summer months, as to be com- 230.67-a mean which is less than paratively of little value as a naviga- that of Italy or southern France, and ble basin.

only about two-fifths of that of Fort Accordingly we find, that whilst the Snelling, Iowa, which is 569.60, notsugar-cane is cultivated in Europe as withstanding the latter is nearly one far north as latitude 36o, in a mean degree further south. annual temperature of about 679, its Dr. Forry also points out the influcultivation in the United States, on ac- ence produced upon vegetable geogracount of the low winter temperature, phy by the unequal distribution of heat is prevented beyond latitude 31°. In among the seasons, as illustrated in the Europe, the olive ranges between lati- four systems of climate demonstrated tude 36° and 44°, that is, in a mean on the same parallels in the northern annual temperature of 660 down to division of the United States; and if we 580, provided the mean temperature of extend the comparison to the Pacific summer is not below 71°, nor that of coast, a fifth system, as has just been the coldest month below 420, which seen, may be enumerated on the same last excludes the United States beyond latitude. Taking the coast of New latitude 35°. For the same reason, England, the region of the great lakes,

and the Pacific coast, the difference be- bility of functions by which organized tween the mean temperature of winter structures accommodate themselves to and spring, varies from 69.67 to a change of physical circumstances. 180.42; whilst in the excessive cli- “In surveying the different regions mates of the regions west of the lakes, of the earth," says our author, “as it and intermediate to them and the were with a coup-d'æil, the mental eye Atlantic, this difference ranges from is equally struck with the dissemblan180.82 to 30°.83; and accordingly we ces and the analogies which appear. find, as already explained, that spring Each climatic zone has a peculiar asand summer are confounded with each pect, the physical circumstances of other, and that the sudden excess of which mould everything with a plasheat renders the progress of vegeta- tic hand. Even man, endowed with tion almost perceptible. Not only is those functions which constitute him a the vernal increase greater in excessive cosmopolite, becomes, in appropriating climates; but, as it supervenes upon a to his wants the objects which sur. lower winter temperature, the effect round him, assimilated in nature. Our produced upon the development of idea of a special climate, then, should vegetation is in an inverse ratio. The embrace all the characteristics in the vernal increase of 30°.83, for example, animal, vegetable, and mineral kingat Fort Snelling, Iowa, comes upon a doms, by which nature has distinguishmean winter temperature of 150.95, ed one locality from another." whilst at Fort Sullivan, on the coast of From remote ages, it is well known Maine, on the same parallel, the in- that the inhabitants of every extended crease of only 170.16 follows a winter locality have been marked by certain temperature as high as 229.95.

physical, moral, and intellectual pecuAs regards the effects of diversity of liarities, serving no less than particuclimate on the distribution of animals, larity of language, to distinguish them our limits will not allow us to enlarge from all other people; but how far Tropical regions, as in the vegetable this result ought jusily to be ascribed to creation, display animate nature in its the agency of the climate is still an ungrandest developments. Both on the determined point. But the influence land and in the sea, animals attain not of climate upon man's organization has only the most enormous magnitude, been noticed from the earliest records but exbibit the most extraordinary and of medicine. This powerful influence diversified forms and colors in nature. is apparent at once in surveying the exWhere else than amidst the profusion ternal characters of the different naof vegetable exuberance teeming with tions of any quarter of the earth. In animal life exhibited within the trop- casting one's eye over our national ics, could the elephant and rhinoceros, legislature, the same diversity of phythe ostrich and cassowary, the boa and siognomy is apparent. The general crocodile, exist? And in illustration of countenance of each State's delegathe design evidenced on every hand, tion is indeed a pretty sure criterion to where but in countries so productive of judge of its comparative salubrity. animal life should we discover the We can at once distinguish the ruddy ferocity of the tiger and the poison of inhabitant of that mountain chain, the serpent, as wise checks upon ex- where health and longevity walk hand cessive increase ?

in hand, where Jefferson and Madison One of the most interesting problems inhaled its cheerful and invigorating in history is, the geographical distribu- breezes, from the blanched resident of tion of the human family ; but this our southern lowlands--those fair and subject would of itself occupy a vol- inviting plains whose fragrant zephyrs ume. Man alone can be truly re- are laden with poison, and the dews of garded as a cosmopolite. Although whose summer evenings are replete more readily assimilated with particu- with the seeds of mortality. As in the lar climates than any other animal, yet smiling but malarial plains of Italy, the inhabitants of the middle latitudes,

“ In florid beauty, groves and fields like other animals as well as plants, in consequence of their habitual ex

appear,

Man seems the only growth that dwinposure to extremes of temperature and

dles here." consequent greater vital energy, manifest, in the highest degree, that plia. “Death here,” says Macculloch,

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speaking of malaria in Italy, “walks arisen both in Egypt, under the tropic,
hand in hand with the sources of life, and in Scandinavia, under the polar
sparing none; the laborer reaps his circle.
harvest but to die; or he wanders amid Our author propounds the two fol-
the luxuriance of vegetation and lowing questions-Does the climate of
wealth, the ghost of a man, a sufferer a locality, in a series of years, undergo
from his cradle to his impending any permanent changes? Does the
grave; aged even in childhood, and climate of our north-western frontier
laying down in misery that life which resemble that of the Eastern States on
was but one disease. He is even driven their first settlement ?
from some of the richest portions of this It has been much debated, whether
fertile yet unhappy country; and the the temperature of the crust of the
traveller contemplates at a distance earth or of the incumbent atmosphere,
deserts, but deserts of vegetable wealth, has undergone any perceptible changes
which man dares not approach,-or he since the earliest records, either from
dies."

the efforts of man in clearing away
Macculloch gives a deplorable pic- forests, draining marshes, and cultivat-
ture of the degeneracy produced in man ing the ground, or from other causes.
by a residence of successive genera. As the earth is continually receiving
tions in some of the malarial districts heat from the sun, it follows that, if no
of Italy. Young women, before the caloric is thrown off into surrounding
age of twenty, have often the aspect space, its mean temperature must be
of that of fifty, while in men, the age continually augmenting. It has ac-
of forty is equivalent to sixty in healih- cordingly been inferred that the in-
ier climates. Not only does the stature crease of temperature is at the rate of
become reduced, but deformities are 1° in eighty years; and thus the
frequent. In our own country, along changes of climate alleged to have
the frontiers of Florida and the south- gradually supervened during successive
ern borders of Georgia, as witnessed ages in many countries, and particu-
by our author, as well as in the low- larly in the west of Europe, are at-
lands of our southern States generally, tempted to be explained. But many
may be seen deplorable examples of the geologists, on the other hand, main-
physical, as well as mental and mo- tain the doctrine, (on the supposition
ral deterioration induced by malaria. that the surface of the earth had a
In the Pontine marshes of Italy, the higher temperature at the period of the
residents have the appearance of walk- formation of the older rocks), of a de-
ing spectres. The moral and intellec- creasing superficial temperature as the
tual faculties become degraded. In result of radiation. It has been satis-
the Maremma of Tuscany, absolute factorily demonstrated by La Place,
idiotism is common. The picture however, that since the days of Hip-
drawn by Monfalcon of the moral con- parchus, an astronomer of the Alex.
dition of the people in some of these andrian school, who flourished about
pernicious districts, is truly frightful. two thousand years ago, the tempera-
În the catalogue of their vices, he ture of the earth cannot have increased
names universal libertinism, abortion, or decreased a single degree, as other-
infanticide, drunkenness, a disregard of wise the sidereal day must have be.
religion, and whilst their murders are come either lengthened or shortened,
common, a large proportion are those which is not the case.
of premeditated assassination. It is In regard to the former and present
also worthy of remark, that whilst the temperature of the earth, M. Arago
deaths are increased and the mean du- arrives at the conclusion, that in Eu-
ration of life diminished, the ratios of rope in general, and in France in par-
marriages and births are augmented, ticular, the winters were, in former
it being not uncommon for one woman ages, at least as cold as at present,
to have had three, four, or even five an opinion founded upon the alleged
husbands.

fact of the congelation of rivers and At the same time, it is manifest that seas at a very ancient period. He thinks political institutions and social organi- that the conquests of agriculture, such zation often struggle successfully as the opening of forests and the drainagainst climatic agency; for heroes, ing of marshes, as well as the confinemen of genius, and philosophers, have ment of water-courses to their chan

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