1835.] 



the Ground at Various Depths. 



457 



1st. of July 1834. The monthly means of these are the 

 following : — 



1833. July . . 

 August . 

 September 

 October . 

 November 

 December 



1834. January . 

 February . 

 March . 

 April . . 

 May . . 

 June . . 



If we take the mean of the result of each thermometer, 

 then will the mean annual temperature of the ground at 

 Stockholm be, 



At the depth of 1 foot 43*880 



2 feet 43-898 



3 feet 43-906 

 Whence, it follows that the mean temperature of the ground, 

 at least to the depth of three feet, is independent of the 

 depth ; and in all probability this proposition will be correct 

 for all depths, till the point where all variation of tempera- 

 ture ceases. 



The table shews, besides, that temperature at the end of 

 September and the end of March, or at the time of the 

 vernal and autumnal equinox, is the same at all these 

 depths. 



Although more observations may be required to settle 

 these two propositions, I have, nevertheless, thought it 

 proper to draw the attention of meteorologists to them that 

 they may try their accuracy in other places. 



This mean temperature of the earth is greater than the 

 mean temperature of the air at Stockholm, which is only 

 42-24 F. 



