and the Distribution of Heat over the Globe. . ‘^5 
The quantity of heat which any point of the globe receives, 
is much more equal during a long series of years than we would 
be led to believe from the testimony of our sensations, and the 
variable product of our harvests. In a given place, the num- 
ber of days during which the N.E. or S.W. winds blow, pre- 
serve a very constant ratio, because the direction /ind the force 
of these winds, which bring warmer or colder air, depend up- 
on general causes, — on the declination of the sun, — on the con- 
figuration of the coast, — and on the lie of the neighbouring 
continent. ' It is less frequently a diminution in the mean tem- 
perature, than an extraordinary change in the division of the 
heat between the different months, which occasions bad harvests. 
By examining between the parallels of 47° and 49° a series of 
good meteorological observations, made during ten or twelve 
years, it appears, that the annual temperatures vary only from 
1®. 8 to 2^.7; those of winter from 8 6 to 5^.4 ; those of the 
months of winter from 9® to 10®. 8. At Geneva, the mean tem« 
peratures of twenty years were as follows : 
Mean 
Mean 
Years. 
Temp. 
Years. 
Temp, 
1796, 
49°.3 
1806, 
5r.4 
1797, 
50.5 
1807, 
49.3 
1798, 
50.0 
1808, 
46.9 
1799, 
48.7 
1809, 
48.9 
1800, 
50.5 
1810, 
51.1 
1801, 
51.1 ’ 
1811, 
51.6 
1802, 
50.9 
1812, 
47.8 
1803, 
50.4 
1813, 
48.6 
1804, 
51.1 
1814, 
48.2 
1805, 
47.$ 
1815, 
50.0 
Mean oIp 20 Years, 
49°.67 
If, in our climates, the thermometrical oscillations are a 
sixth part of the annual temperature, they do not amount to 
one twenty-fifth part under the tropics. I have computed the 
thermometrical variations, during eleven years, at Paris, for 
the whole year, the winter, the summer, the coldest month, the 
warmest month, and the month which represents most accurate- 
ly the annual mean temperature ; and the following are the re- 
sults which I obtained ; • 
