* Pom [ 300 } 
According to Barton, the climate to the west of the Alleghany mountains 
is much warmer than that on the east, or Atlantic side, where the 
plants exist 3° or 4° higher up on the west than on the east side of the 
range. It is probable, however, that this difference does not extend higher 
up than Lake Erie, in 42° north latitude ; ; for, both beyond Lake Superior 
and Hudson’s Bay, the earth is said to be constantly frozen at three feet from 
the surface ; a phenomenon which also occurs in Siberia, about 7 river 
Lena, in about 62° north latitude, near the town of Jakutsk ; while, in Lap- 
— in 70° near Vadsoe, the temperature of the earth is found to be: “i much 
s 3° or 4° above the freezing point ; whence it appears that the climate ot 
the veto of Europe is warmer than that of the same latitudes in Asia and 
ca. We therefore shal] not be far away, if we conclude that the 
isothermal lines bend ie rds the tropics in Europe, and towards the poles 
in Fartary and Amer 
AS we approach the segtnati there appears to be little difference in the 
mean temperature of the year, either in the new or old world. 
+ 
; Of the old world. 
— mean temperature of Senegal is 79.7° in lat. 24° 30' N. 
Madras is 80.4° i y lat. 13° 5'N, 
of Bativia't is 77.4° in lat. 6° 10'S. 
of Manilla is 78.0° i in lat. 15° N. ; 
Of the new world 
The mean temperature of Cumana is 81.6° in lat. 10° 27' N, 
; of the Antilles is 81.6° in lat. 15° N. 
of Vera Cruz is 78.0° in lat. 19° 12’ N. 
of Havana is 78.0° in lat. 23° 12' N. 
ee is probable, however, yon the summers of Asia are more fervid than 
ose of America; for, according to Roxburgh, the mean temperature of 
Madras, in latitnde 13° 5' ied in the month of July, is 89.4°; while 
wd of Cumana, in latitude 10° 27! does not exceed 84.4 
o the south of the equator, the temperature of the east seems to be 
higher than that of corresponding latitudes in the west ; thus, the mean tem- 
‘perature of the Mauritius, in 20° 9! south latitude, has bee een ascertained to be 
“Soe, pte that of Rio Janeiro, in latitude 20° 59’ south, is as low as 74,3° ; 
he cabbage in nearly the same ee in the northern hemisphere, 
it rie Be 77° and 77.99, The le of the western coast of South 
America, as The * the selitis of Peru, in tatitode 10° and 14° south, are affect- 
ed so much by the continual prevalence of clouds and the low temperature 
(59.9°) of the currents setting round Cape Horn, that the mean temperature 
of the year in those parts does not exceed 68° or 69°. Hee the plants 
of Lower Pern®* live in a temperature not edalithae by day, 68° or 72°, and 
by night 59° or 62°. Near the coast Humboldt pt Aref i “alibi teens 
‘ 
* Hence, a!l ot ican plants of Lower i pie should be speedily transferred to ti od 
‘ ee: ses eorological get " = Sp West six aay from 1830 to 1836, th 
- Thean ature is 76.62 -annual, for the cool months, from Ist of 
Gotober 1 to jist ries east hes for the ae Warm months, from Ist of April to 3 30h 
ots 
nt 
