tains, therefore, properly speaking, separates in the north this enor mous territory, a small portion of which constitutes the State of Illinois, from the plateaux projecting to the north, which circumstance must necessarily exercise a decisive influence upon the climate of the State, situated as it is between the 43d and 37th degrees of north latitude, and separated by seven degrees from the Gulf of Mexico.

A sea open at all times of the year separates Europe from the North Pole; and the Mediterranean Sea washes between it and Africa; this will sufficiently account for her moderate climate. A frozen regioL sending during winter its icy blasts after the flying sun, bounds North. America on the north, while her southern coast, penetrated in the sum. mer by the almost perpendicular rays of a burning sun, radiates its accumulated heat to the north. This will explain why a country situated within the same degrees of latitude with Spain and Italy, has cold winters and hot summers.

Illinois has an average temperature, which, if compared with that of Europe, equals that of Middle Germany; its winter is more severe than that at Copenhagen, and her summer as warm as those of Milan or Palermo. Compared with the other States of the Union, Northern Illinois possesses a temperature similar to that of Northern Pennsylvania or Southern New York, while the temperature of Southern Illinois will not differ much from that of Kentucky or Virginia.

As far as we know, exact observations of the state of the weather have not yet been published in Illinois; we, therefore, confine ourselves to the observations of the celebrated Dr. Engelmann, at St. Louis, which at least serve for one part of Illinois. From his observations of 20 years we infer, that at a middle height of the barometer, of 29-477, (105' above the lowest height of water in the Mississippi), the greatest difference in a year (1852) amounted to 1" 5"", and that at a middle temperature of + 51° 8 F. (= + 13° 79 C. = + 10° 13 R.), very great fluctuations prevailed.

25°

At the coldest day, (Feb. 8, 1835,) the thermometer stood F. (31° 6 C.25° 3 R.), while during the hottest days in July, 1833, 34, 38, and '41, and in August, 1834, the mercury indicated a little more than +100° F., (= + 38° C. + 30° R.), making a difference of 125° F., (= 69° 4 C. 55° 5 R.) Very great and rapid changes often take place in the temperature; thus, the

=

22° 5 R.)

temperature from the 16th to the 17th day of March, 1852, fell, within 17 hours, about 51° F., (= 28°3 C. As for the rest, the thermometer very rarely falls below 0 F. (= -17° 7 C. = 14° 2 R.); on Jan. 19th, 1852,* the coldest day for 20 consecutive years, the mercury ranged - 12° F. (24° 4 C. 19° 5 R.) The lowest temperature is generally above 0 F., and on an average ranges highest in July; then follow June and August; January being the coldest month. The first frost generally appears on the 26th of October, the last on the 6th of April, 203 days thus intervening between the first frost in autumn and the last in spring. The earliest frost appeared on Oct. 4th, 1836, and the latest, May 2d, 1851.†

The prevailing winds are either western or south-eastern. Storms generally come from the west or north-west, in the summer sometimes from the south. The severest storms are those coming from the west, as, on considering that they traverse the entire space between the Rocky Mountains and the Mississippi, within 24 hours, and reach the Atlantic coast within the next 24 hours, will be placed beyond a doubt. A clear sky and dry air prevail while they sweep over the Mississippi Valley, and not before having reached the east, will they be accompa

The winter of 1855-6 alone, which reigned with almost unexampled rigour throughout the United States, makes an exception; we here subjoin a report of the state of the thermometer on the coldest days of the winter, in the folowing places in Illinois:

On January 4th, 1856, at Aurora, Kane Co., 22 degrees below zero; at Sterling, Whiteside Co., 26°; at Dixon, Lee Co., 23°; at Sycamore, De Kalb Co., 24; at Waukegan, Lake Co., 21°; at Moline, Rock Island Co., 18°. On January 5th, at Elgin, Kane Co., 26°; at Moline, 14°; January 6th, at Moline, 30°; January 8th, at Sterling, 21°; at Springfield, Sangamon Co., 20°; at Rock Island, 22°; at Bloomington, McLean Co., 18°; at Belvidere, Boone Co., 22°; at Macomb, McDonough Co., 17°; at Elgin, 18°; at Moline, 20°; at Oquawka, Henderson Co., 25°; at Peoria, 14°. January 9th, at Springfield, 24°; at Chicago, 24°; Alton, Madison Co., 22°; at Aurora, 30°; at Geneseo, Henry Co., 29°; at Jerseyville, Jersey Co., 20°; at Macomb, 20°; at Mendota, La Salle Co., 28°; at Monmouth, Warren Co., 28°; at Morris, Grundy Co., 20°; at Paris, Edgar Co., 30°; at Peoria, 20°; and at Sterling, 21°.

In the summer of 1850, while the temperature of St. Louis ranged very high, that of St. Clair Co. was continually lower, by about 2° R., than the former, which difference was probably in consequence of the calcareous soil of the city.

nied with heavy showers of rain; which latter fact we may account for by the condensation of the vapours abstracted by them from the Mississippi Valley, coming in contact with the Alleghany Mountains.

Rainy days there were in 1838 but 78; in 1836, however, 115; there are, on an average, 89 in every year, with a quantity of rain amounting to 42 inches, the smallest portion of which (2") falls in January; the quantity of rain falling increasing with every succeeding month, until in June it reaches the height of 6". More than 4 inches of rain fell within 24 hours, June 23, 1852.

The first fall of snow generally takes place in November, often, however, not before December; the last, in March, it occurring but very rarely in April. The greatest quantity of snow which fell in a single month, (December, 1839, and December, 1846,) amounted to scarcely 1" 5. Thunderstorms there were on an average 49; beautiful days, 137; changeable days, 180; days without sunshine, 45.

Upon comparing these results with the observations made in 1852, in Wisconsin, at eight different places, the observation made at one of which, to wit, at Beloit, near the Illinoisian frontier, half way between the Mississippi and Lake Michigan, may be considered as valid for the northern part of Illinois also; we find the thermometer ranging between 29.597 and 28.665, being a difference of 0.932, while in the south the same amounted to 1.584; an average temperature reigns there of 47° 421 F. (+8° 1 C. +6° 5 R.), being 7° 1 F. (=

=

4° C. 3° 1 R.) less than in the south. cury indicated — 18° F. (— — 27° 7 C. fore 6° F., ( 3° 3 C.

=

On the coldest day the mer-22°1 R.), and there

2° 6 R.) less than at the south; and on the

(=3° hottest day 93° F. (= + 34° C. = + 27° R.) and therefore only + 2° F. (1° 1 C. 0° 9 R.) less than in the south. Here we must remark that the winter at that place was unusually cold. It rained 40 inches, 2 inches less than at the south, which difference, as already observed, was created by a single day's rain. The prevailing winds were north-west by north, and south-west.

From the direction of its hills and rivers, which generally run from north-east to south-west, a plain forms, gently sloping to the southwest; in this plain the rivers have worn channels from 60 to 200 feet deep; being dammed up at one side by a terrace-like, rising bank, they inundate the opposite plain to a considerable depth, overflowing

it from winter to summer, and producing a luxuriant growth of grass; causing also the intermittent fever, the principal sickness of the country, which, however, only seizes the incautious settler, at places near the river; and never, except in very rainy years, visits the settlers on the ocean-like, undulating prairies.*

That the channels have gradually sunken we may distinctly see, on the shores of the Upper Mississippi, walls of rock rising perpendicularly, upon the sloping banks of which extend from Lake Pepin to below the junction of the Wisconsin with the Mississippi, as if they were walls built of equal height by the hand of men. Wherever the river describes a curve, walls may be found on the convex side of the latter. Here, the force of the river, ere it had yet excavated its channel, was broken, and the river, tired of being resisted, turned against the other side; not, however, without causing some damage to the rock which it washed; just as at the present day the river may be seen undermining its steep, rocky bank, above and below St. Paul, in Minnesota.

The upper coal formation occupies three-fifths of the State; commencing at 41° 12′ north latitude, where, as also along the Mississippi, whose banks it touches between the places of junction of the Illinois and Missouri Rivers, it is enclosed by a narrow layer of calcareous coal. This immense co: 1-field extends south-easterly beyond the Wabash and Ohio Rivers, far into the States of Kentucky and Ohio. The shores of Lake Michigan, and that narrow strip of land, which, commencing near them, runs along the northern bank of the Illinois, towards its south-western bend, until it meets Rock River, at its junction with the Mississippi, belongs to the Devonian system; the residue of the northern territory consists of Silurian strata, which, containing the rich lead mines of Galena, in the north-western corner of the State, rise at intervals in conical hills, thus giving the landscape a character different from that of the middle or southern portion of the State.

Over these various geological formations, underlaid at intervals by beds of sand, a process of putrefaction, which, for thousands of years

*The attention of those readers wishing more minute information regarding the state of health in Illinois, is called to the chapter treating of that subject in particular.

continued uninterrupted, has spread the richest humus, that, rather too luxurious for other grains, yields the most abundant harvests of Indian corn, the staple commodity of agriculture.

Remarkable are also those large blocks of granite and other primitive rocks, which are scattered along the banks. Since the nearest beds of primitive rocks first appear in Minnesota, and the northern part of Wisconsin, their presence can only be accounted for by assuming, that at the time the State of Illinois was covered with water, they were floated down from the north, enclosed and supported by masses of ice, which no sooner melted than the rocks sunk to the bottom, maintaining, as old settlers, their present position, whilst the work of excavation of the valleys, ravines, and channels by the water, was going on; whereas the lighter masses of earth, driven down the river, were deposited at the southern corner of the State, near the mouth of the Ohio, or contributed to the formation of the Mississippi Delta; since, in fact, the later alluvial land of the Lower Mississippi Valley reaches up the river to that point.

On the banks of the Illinois River, the pebbles rounded by the water may be found covered with a yellowish crust, as if they were baked together. These are the later fresh water calcareous strata, continually deposited before our eyes by the water.

The vegetation of the State forms the connecting link between the Flora of the northeastern States, and those of the Upper Missisippi, exhibiting, besides the plants common to all States lying between the Mississippi and Atlantic Ocean, such as are, properly speaking, natives of the western prairies; not being found east of the Alleghany Mountains. Immense prairies of grass, interlaced with groves, and stretching, principally, along the water-courses, cover two-thirds of the entire area of the State in the north, while her southern part is garnished with tufts of massive thickets, greatly diversifying the otherwise somewhat monotonous landscape.

In order to obtain a view of the variety of the vegetable creation of the State, we invite the reader to accompany us on a summer excursion.

The large, scattered, village-like formation of the smaller and middle towns, and the want of a pavement, render it possible for us to herbalise in the very town, from the moment we have stepped outside our