Agricultural Chemistry. 121 
amount of manganese reduced. The basic or acid nature of the slag has 
also an important influence on the amount of the reduced manganese—it 
's easily reduced from a basic slag, but with considerable difficulty from 
an acid slag. Richter gives analyses of Spiegeleisen from Jauerburg in 
Curniola and Theresienthal in Bohemia : 
Jauerburg, Theresienthal. 
Sulphur, 0-073 ves 
Silicon, 1902 2°732 
Manganese, 7578 22°183 
Carbon, : 2°311 
The extraordinary amount of manganese found in the specimen from 
Theresienthal so influenced the properties of the iron, that it was not 
Magnetic, and had not the power to throw down copper from a solution 
of chlorid of copper, it simply reduced it to sub-chlorid. 
Richter further remarks that the same mass of iron may contain more 
Manganese in one part than another, this is due to the tendency man- 
Baese hasto separate from the fused mass, and the upper portion of a 
pig” may thus contain more manganese than the lower portion.—JB. u. 
H, Jahrbuch, xi, 295, 
iy, AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 
1. On the Nature of the Gas produced from the Decomposition of Car- 
bonic Acid by oo tothe Tao ; by M. Bousstneauit.—An 
wateresting paper in Ann. Sci, Nat., (Bot.), 4th series, xvi, p. 1-27, 1862. 
‘ "ring to the history of discovery in respect to the relations of plants 
of the atmosphere, Boussingault remarks, that Bonnet first took notice 
the emission of air from the surface of leaves; Priest] ized 
he 
Plant,—not considering, what is now obvious, that the substance of the 
ey did not contain, and therefore could not have furnished, any thing 
this quantity of nitrogen. ; 
ern times, Daubeny was unable to obtain from leaves oxygen 
888 free from azote 
_leaves of a common Pond-weed (Potamogeton perfoliatus) in 
beg slightly impregnated with carbonic acid, found the first day 15°70 
hie rent of the gas eliminated was nitrogen; the second, 13:79; the 
l, 12-00; the fourth, 10°26; the fifth, 9°53; the sixth, 8-15; the sev- 
bes 434; the eighth, 2°90. That is, the oxygen gas grew purer and 
AM. Jour, Sci.—Srconp Szrtss, Vou. XXXV, No. 103.—Jan., 1863. 
16 
