Miscellanies. 



205 



of 567 feet 7 inches, the temperature was found to be 61°.52 F., thus 

 giving for 1°.8 F. 101 feet 2.6 inches. It thus results from observa- 

 tions made at various depths of from 567 feet to 1312 feet, that the 

 rate according to which the temperature increases with the depth in 

 the chalk formation, appears to be regular in the Paris basin It 

 would be important to ascertain, by experiments made with care, if, 

 in the middle and lower parts of the secondary formations, the tem- 

 perature increases with the depth at the same rate; and M. Walfer- 

 din now proposes to direct his attention to this point. — Comptes Reri' 

 dus, IGthAvril, 1838.— lb. 



34. Extract of a Letter from M. Erman, junior, to M. Arago, 

 upon the Temperature of the Ground in Siberia. — I hope you will 

 look with some interest at those parts of my historical journal which 

 treat of the climate of Northern Asia ; and in relation to this subject, 

 I beg to direct your attention to the 242d and following pages. I 

 have there given the result of the data obtained regarding the climate 

 of the town of Jakouzk. The depth of a well which M. Schergin, a 

 merchant in the town, had then excavated to the depth of 50 feet 

 (English,) in the hope of finally reaching strata which were not froz- 

 en, and which would be capable of supplying water, was always, 

 when I made trial, at the temperature of — 6° R. equal to 18°.5 Fahr. 

 The temperature of the surface of the soil should not at the time have 

 exceeded this degree of cold, since the latitude of the place was 

 62° r29". This result appeared to me eminently paradoxical ; but I 

 have since confirmed it, by calculating observations made on the tem- 

 perature of the air in the same town, during many consecutive years, 

 with thermometers which I have carefully compared with my own. 

 Some results are subjoined : 



