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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.
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
follows that the temperature of its of Pui, at about the same elevation,
to the north or south, we soon discover
VOL. XI.-N0. LIII.
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
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,
speaking of malaria in Italy, “walks arisen both in Egypt, under the tropic,
the efforts of man in clearing away
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