a 
THE AIR OF THE SOIt. 219 
Boussingault and Lewy. (Mémoires de Chimie Agricole, 
etc., p. 369.) 
~3 [SS 
s§ (8S 
to'|"=s 
ST |/SSS | Composition of the 
SS x 2-3 | air in the soil zn 100 
SS SSx| parts by volume. 
£8 [73" | ae 
QS e/g ar- Dlg 
Se (SB | donic | OF |Nelro- 
S” ISS | aca. | YIM | gen. 
Sandy subsoil of forest Sey GAP ei A ee 4416} 14 | 0.24 
Loamy ‘* a NL Pied eats ooh Bie lan sect oe 3530} 28 | 0.79 | 19.66; 79.55 
Surface soil SPE Sts ei ebie sited SHES wetaa A nae 5891 57 | 0.87 | 19.61] 79.52 
Clayey ‘“‘ of artichoke field ................. 10310} 1 | 0.66 | 19.99] 79.35 
Soil of asparagus bed not manured for one year| 11182 86 | 0.%4 | 19.02! 80.24 
** newly manured.......... 11182) 172 | 1.54 | 18.80) 79.66 
Sandy soil, six days after manuring. . .{of rain} 11783) 257 | 2.21 
three days| 11783) 11- 9.%4 | 10.35) 79.91 
Vewetable SMM COMBO: rds Seen ve eee eee 21049, 772 | 3.64 | 16.45) 79.91 
Composition of air 
|above the soil zn 100 
parts. 
—.-. 
height of 14 inches. 
ee Ox- | Nitro- 
acid. | 9 | ger. 
en aer over one acre to 
Cubic feet of air over one 
acre to height of 14 inches. 
Cubic feet of carbonic acid 
or 
So 
oe) 
~ 
o 
12 | 0.025/20.945/|79.030 
The percentage, as well as the absolute quantity of car- 
bonic acid, is seen to stand in close relation with the or- 
ganic matters of the soil. The influence of the recent 
application of manure rich in organic substances 1s strik- 
ingly shown in case of the asparagus bed and the sandy 
soil. The lowest percentage of carbonic acid is 10 times 
that of the atmosphere a few feet above the surface of the 
earth, as determined at the same time, while the highest 
percentage is 390 times that proportion. 
Even in the sandy subsoil the quantity of free carbonic 
acid is as great as in an equal bulk of the atmosphere ; 
and in the cultivated soils it is present in from 6 to 95 
