Soir ANALYSIS. 357 

Bodenkunde employs a 2mm. round-hole, but also analyses 
the finest particles separated by washing ; Grandeau and 
the French Comzté Consultatef des Stations Agronomique s 
use a I mm. woven sieve; and Petermann, in his examination 
of the Belgian soils, does the same. The Committee suggest 
3 Mm. as a convenient size; lumps of earth can be readily 
reduced to that diameter, whereas sifting down to 1 mm. 
involves either so much crushing of lumps of earth as 
results in considerable fracture of the stones, or else wet 
sifting. The quarter-inch square mesh sieve passes in some 
cases a large proportion of hard stones, that are further 
reduced with much difficulty, and yield unweathered material 
not likely to be serviceable for plant nutrition for many 
years. The further grinding is recommended to obtain 
material from which a small sample for analysis can be fairly 
drawn. 
(4) Determination of Morsture——The sample shall be dried 
in the steam-oven to constant weight. 
(5) Determination of Loss on Lgnition.—The result shall be 
so expressed as not to include the carbon dioxide expelled 
from the carbonates, or the moisture previously determined. 
(6) Determination of Nitrogen.—Unless otherwise specified, 
the nitrogen shall be determined by Kjeldahl’s method. 
(7) Determination of Carbonate of Ltme.—The carbon 
dioxide evolved on treatment of the fine earth with acid is 
to be calculated as carbonate of lime. This is regarded as a 
convenient measure of the “available basicity” of the soil, 
without discriminating between carbonates of lime and 
magnesia. 
(8) Determination of “ Total” Mineral Constituents.—The 
fine earth is to be boiled with strong hydrochloric acidin an 
open flask for a short time, in order that the acid may attain 
constant strength, and digested at the ordinary water 
bath or steam oven temperature for 40—48 hours, the 
flask being loosely stoppered. In this solution the phos- 
phoric acid and potash are determined, and other mineral 
constituents as desired. The object of the Committee 
is to obtain as thorough an extraction of the soil as 
is possible short of ultimate analysis. The time of the 
