284) Prof. Bischof on the Temperature of 



■with the height, from Wahlenberg's single observations on the 

 temperature of the Simss Alps,* von Buch''s in the Canary 

 Islands, f Forchhammer''s on the Faroe Islands^ J and Kern's 

 on the Swabian Alps.§ But the results of these attempts were 

 as unsatisfactory as Kamtz's calculations |] on Wahlenberg's 

 observations, which gave the very improbable result, that at a 

 height of 2700 feet, the temperatures of the air and of the soil 

 are equal, but that at the height of 32,000 feet, the soil is 

 1 1°.25 warmer than the air. 



1 have myself observed the temperature of a great number 

 of springs in the Alps ; but it would be of no assistance to us, 

 in our present object, to communicate them here. That which 

 resulted from the one year's observations in the Siebengehirge, 

 on a small scale, was there seen on a large scale. For example, 

 in the neighbourhood of Grindelwald, namely, at the foot of 

 the Mettenberg and of the Eiger, I observed no less than 

 twenty-two springs, whose temperatures were between 37'.40 

 50°.00, and the coldest were precisely those which were on the 

 lowest level. What conclusions can be drawn from these on 

 the temperature of the soil, and on the decrease of tempera- 

 ture ? 



Chap. XIX. — What Conclusions may be drawn from the Observa- 

 tions hitherto made on the Increase of T'emperature towards the 

 Interior of the Earth ? 



In the foregoing chapters we have become acquainted with 

 the various causes which may modify the increase of tempera- 

 ture towards the interior of the earth. Is it then surprising 

 that the results should be so very various, frequently bearing 

 no comparison to each other ? 



Kircher H seems to have been the first who took notice of the 



* De "Veget. et Cliiti. in HelveK septentr., p. Ixxvii. § 87. 

 + PoggendorflF's Annal. xii. 407. 



X Karsten's Archiv fiir Mineralogie, &c. &c. ii. 199. See also PoggendorfF's 

 Annal. xxxv. 213. 



§ Kastner's Archiv flir Chem. und MeteroL iv. 42. 



II Lehrb. der Meteorol. ii. 200. 



IT Mundus Subterraneus, 1664. fol., vol. ii. p. 184 and 185. 



