S75 
and the Disirlhution Heat over the Globe. 
lietween the tropics, the Cordilleras form the centre of the 
civilization and industry of Spanish America. They are inha- 
bited to the height of 4000 metres, (13,120 feet) ; and a small 
number of observations made on the back of the Andes, gives a 
sufficiently accurate idea of the mean temperature of the year. 
In Europe, on the contrary, in the temperate zone, the high 
mountains are in general little inhabited. The descent of the 
isothermal line of 52°, causes to cease the cultivation of crops of 
grain, at the point where they begin in the Cordilleras. Sta- 
tionary habitations are rare above 2000 metres (6560 feet) of 
elevation^ and in order to judge with any precision of the mean 
temperature of the superincumbent beds of air, we must unite 
at least 750 thermometrical observations made in the course of 
a year 
* Elevations of 400 metres (1312 feet) appear to have a very sensible influence 
on the mean temperature, even when great portions of countries rise progressively. 
In order to establish this point, I have examined the temperatures of places si- 
tuated almost on the level of the sea, and under the same parallels. 
Lat. 
Elevation 
Mean Temp. 
in Feet, 
Buda, » - , 
47!29 
512 
51.08 
Paris, ... 
48.50 
116 
51.08 
Vienna, - - - 
48.12 
551 
50.54 
Manheim, 
49.20 
384 
50.18 
Whence, in the longitudes of Paris arid Buda, and between the latitudes of 47® 
and 48°, and almost at the level of the sea, the mean temperature is from 50°.9 to 
51°.44. 
Under the same longitudes, we have,— 
Elevation 
in Feet. 
Mean Temp, 
Geneva, 
- 
1177 
49!28 
Zurich, 
1437 
47.84 
Munich, 
- 
1711 
50.74 
Berne, 
. 
1755 
49.28 
Marschling, 
- 
1834 
51.98* 
Coire, 
- 
1991 
48.92 t 
By taking the means of these results, we cannot mistake the influence of small 
elevations^ or of very extensive plateaus^ on the decrease of the mean temperature. 
* Heated by the winds of Italy. 
+ In spite of the winds of Italy. 
