10 DR. R. ANGUS SMITH ON THE 



air from close places was examined. Those of Dr. Frank- 

 land are also corroborative. 



It will be seen that I now consider 20*9 as representing 

 air very inferior only^ leaving out any reference to that from 

 great heights. Even with this liberal allowance I found 

 only lO'bj per cent, of the specimens of the air of mines 

 capable of comparing with normal air. 



Air deviating from the adopted Standard. 



Air from Heights. 



Oxygen. 



Dalton Helvellyn 20-64 



,, • 20-63 



From a height of 9600 feet 207 



„ „ 15,000 „ 20*62 



Bruiiner_ Faulhorn ao'Qi 



Boussingault 548 metres high 20*7 



„ Santa F6, 2643 20*65 



Air brought by Green from a height of 11,300 feet 21* 



Frankland Chamounix 20*894 



„ Top of Mont Blanc 20*963 



„ Grrand Mulets 20*802 



Berger Jura and other mountains 20*3 



to 21*63 



Configliachi Simplon 21* 



Mean 20*818 



I leave out some under 20*2, and still we have a rather 

 curious result — a lower number bn the hills than on the 

 plains. I do not profess to be fully satisfied with these 

 results ; we require a few hundred^ or at least a few dozen 

 analyses ; still these statements are before us_, and cannot 

 be removed without much labour. The results of Frank- 

 land and Boussingault especially are striking, and require 

 an explanation. Let us again compare results obtained by 

 Dumas and Boussingault (Annales de Chimie, 1841). 



