Part 4 (1/2)
The mean temperature of each month during the above years, is as follows:
Deg. Hund.
January 30 62 February 38 65 March 43 13 April 58 47 May 62 66 June 74 47 July 78 66 August 72 88 September 70 10 October 59 00 November 53 13 December 34 33
The mean temperature of the different seasons is as follows:
Winter, 34.53--Spring, 54.74--Summer, 74.34--Autumn, 60.77.
The greatest extremes of heat and cold during my residence of eighteen years, in the vicinity of St. Louis, is as follows:
Greatest heat in July 1820, and July 1833, 100 degrees. Greatest cold January 3d, 1834, 18 degrees below zero,--February 8th, 1835, 22 degrees below zero.
The foregoing facts will doubtless apply to about one half of Illinois.
This climate also is subject to sudden changes from heat to cold; from wet to dry, especially from November to May. The heat of the summer below the 40 of lat.i.tude is more enervating, and the system becomes more easily debilitated than in the bracing atmosphere of a more northerly region.
At Marietta, Ohio, in lat. 39 25' N. and at the junction of the Muskingum river with the Ohio, the mean temperature for 1834, was 52 degrees, four-tenths; highest in August, 95 degrees,--lowest, January, at zero. Fair days 225,--cloudy days 110.
At Nashville, Tenn. 1834, the mean temperature was 59 degrees and seventy-six-hundredths; maximum 97, minimum 4 above zero. The summer temperature of this place never reaches 100. On January 26th, 1832, 18 degrees below zero. February 8th, 1835, 10 below zero.
The putting forth of vegetation in the spring furnishes some evidence of the character of the climate of any country, though by no means entirely accurate. Other causes combine to advance or r.e.t.a.r.d vegetation. A wet or dry season, or a few days of heat or cold at a particular crisis, will produce material changes.
The following table is constructed from memoranda made at the various dates given, near the lat.i.tude of St. Louis, which is computed at 38 30'. The observations of 1819 were made at St. Charles and vicinity, in the state of Missouri. Those of 1820, in St. Louis county, 17 miles N.
W. from the city of St. Louis. The remainder at Rock Spring, Illinois, 18 miles east from St. Louis. It will be perceived, the years are not consecutive. In 1826, the writer was absent to the eastern states, and for 1828, his notes were too imperfect to answer the purpose.
In the columns showing the times of the first snows, and the first and last frosts in the season, a little explanation may be necessary. A ”light” snow means merely enough to whiten the earth, and which usually disappears in a few hours.
Many of the frosts recorded ”light” were not severe enough to kill ordinary vegetation.
Peach &
Strawberries
Blackberries
Apple
Apple
Red bud
in
in
leaves
trees in
Year.
in blossom
blossom.
blossom.
begin to
blossom.
put forth
=====+==========+============+============+=========+=========+
1819
April 4.
Not noted.
May 19.
April 15.
April 20.
-----+----------+------------+------------+---------+---------+
April 14.
May 10.
1820
No peach
April 2.
fall off
Mar. 25
April 15.
B.
17.
-----+----------+------------+------------+---------+---------+
April 26.
1821
No peach
April 30.
May 21.
April 24.
May 3.
B.
-----+----------+------------+------------+---------+---------+
1822
April 5.
April 25.
May 10.
April 18.
April 22.
-----+----------+------------+------------+---------+---------+
1823
April 19.
April 26.
May 20.
April 15.
April 28.
-----+----------+------------+------------+---------+---------+
1824
April 20.
April 28.
May 18.
April 20.
April 29.
-----+----------+------------+------------+---------+---------+
April 3.
1825
Mar. 25.
Ripe
May 8.
Mar. 30.
April 5.
May 17.
-----+----------+------------+------------+---------+---------+
1827
April 4.
April 10.
May 15.
April 4.
April 13.
-----+----------+------------+------------+---------+---------+
1829
April 20.
April 24.
May 20.
April 20.
April 26.
-----+----------+------------+------------+---------+---------+
1830
April 1.
April 5.
May 9.
April 1.
April 9.
continued
Gra.s.s
Oaks and
First
Last
First
green in
other forest
snow on
frost in
frost in Year.
prairies.
trees
approach
Spring.
Autumn.
put forth
of winter.
leaves.
=====+=========+============+============+============+==========
1819
April 18.
Half size
Oct. 8. few
May 18,
Sept. 23.
May 19.
flakes.
very light.
-----+---------+------------+------------+------------+----------
April 22.
Oct. 24. few
June 1,
Sept. 20.
1820
April 10.
full size
flakes. Nov.
very light.
Oct. 8,
May 7.
11 3 inches.
ice.
-----+---------+------------+------------+------------+----------
Ap. 26 to
Nov. 8.
April 18,
1821
April 26.
May 3. f.
2- in.
severe.
Oct. 8
grown 22
May 9, light
-----+---------+------------+------------+------------+----------
April 29.
Nov. 16,
April 16,
1822
April 10.
full size
light.
severe, ice.
Oct. 13.
May 14.
-----+---------+------------+------------+------------+----------
1823
April 10.
April 23.
Nov. 1,
April 24.
Sp. 21-2.
light.
Ice 23.
-----+---------+------------+------------+------------+----------
Oct. 21.
1824
April 14.
April 30.
Nov. 7.
May 5.
hard
freeze.
-----+---------+------------+------------+------------+----------
Dec. 11,
Feb. 22.
Oct. 2-3.
1825
Mar. 16.
April 3.
3 inches.
Next.
27th, ice.
Ap. 20, ice.
-----+---------+------------+------------+------------+----------
April 10.
Nov. 25,
May 7,
Sept. 23, 1827
Mar. 25.
full size
light.
light.
light.
April 30.
-----+---------+------------+------------+------------+----------
Nov. 12,
1829
April 24.
April 27.
4 inches.
Not noted.
Sept. 17.
sleet.
-----+---------+------------+------------+------------+----------
begin Ap.
1830
April 1.
5. f. size
May 1.
These observations, upon a comparison with the same parallels of lat.i.tude in the eastern states, show that there is no material difference of climate between the two sections of our country, except that produced by local causes, as mountainous districts, contiguity to the ocean, &c.
A similar error has existed in relation to sudden and extreme changes of weather in the West. People who emigrate to a new country have their curiosity awakened, and perhaps for the first time in their lives become quite observing of such changes. From habitually observing the weather the impression is produced on their minds that there is a marked difference in this climate. Dr. Rush declares that there is but _one_ steady trait in the character of the climate of Pennsylvania--and that is, _it is uniformly variable_, and he a.s.serts that he has known the thermometer fall 20 in one hour and a half. March 26-27, 1818, the thermometer in St. Louis, fell 41 in 30 hours--from 83 to 42. I have no record or recollection of a more sudden change in 18 years. Mr.
Legaux saw it fall in the vicinity of Philadelphia, 47 in 24 hours, and Dr. Drake states that this is five degrees more than any impression ever observed in Cincinnati, in the same length of time. Emigrants from New England and the northern part of New York state, must not expect to find the same climate in the West, at 38 or 40 degrees; but let them remove to the same parallel of lat.i.tude in the West, to Wisconsin, or the northern part of Illinois, and they will probably find a climate far more uniform than the land of their birth.
Prevailing winds modify and affect the climate of every country.
Southwestwardly winds prevail along the Mississippi Valley. The following tabular view of observations made at Cincinnati, by Dr. D.
Drake, for six succeeding years, with so few omissions, that they amount to 4200, will give further ill.u.s.trations of this subject. They have been brought from eight points of the compa.s.s.
OBSERVATIONS.
MONTHS
S.E.
S.
S.W.
N.E.
N.
N.W.
E.
W.
CALM.
===========+======+====+======+======+====+======+====+====+======= January
6
2
13
8
1
21
3
6
6 February
5
1
13
8
1
14
0
5
8 March
10
1
16
11
1
10
0
5
4 April
7
0