114 Progress in Science. [January, 
Silica aur 46 as ate 3¢ ae 56 69°30 
Lime be ae S2 aie oe 50 50 8°50 
Magnesia 310 50 ws oe aie bc 0°55 
Soda Si a 55 ae a6 ae af 13°79 
Potash! |}. < ei Bc ar te 50 3c 1°49 
Alumina .. re Do a6 ye a0 on 3°20 
Oxide of iron (Fe203) .. a 56 ae a0 2°00 
Oxide of antimony .. ee oe 5p Ac 0°29 
Oxide of lead .. oe ot ae os 60 trace 
Phosphoric acid ac So.) Gs 56 Re 0°80 
Loss in analysis oF a are ac on 0°08 
The specific gravity of the glass is 2°430. 
Wagner, in ‘‘Versuchs Stationer Organ,” xiil.,6g to 75, and 218 to 222, 
describes the results of his experiments with kreatine as a source of nitrogen 
for plants. Maize plants grew and developed seeds in a solution in which 
kreatine was the only nitrogenous substance present. The kreatine was 
absorbed unchanged, and was detected in the plants. Wagner refers to the 
fa& that Hampe had found that urea is absorbed unaltered by plants. The 
same observation was made by Dr. C. A. Cameron in 1857, and was reported im 
the ‘* Transactions of the British Association” for that year, in the ‘* Chemist,” 
for November, 1858, and in the ‘* Repertoire de Chemie, Pur et Appliqué,’ 
Paris, December, 1858. Dr. Cameron finds that plants can absorb unchanged, 
and apparently derive nitrogen from, potassic nitrite, potassic cyanurate, and 
potassic ferrocyanide. 
An examination of the gases occluded in coal forms the subject of a paper 
by Dr. E. Meyer. Lumps of hard and compact Zwickau coals (Saxony) the size 
of a walnut were put into a flask, previously partly filled with thoroughly well- 
boiled and hot distilled water; the flask was next closed with a perforated 
caoutchouc stopper wherein a glass tube was fitted, which, serving as gas con- 
veying tube, was carried into a vessel filled with water deprived of air. The 
apparatus thus arranged was kept at boiling heat for some time in order 
thereby to eliminate the film of air which adheres mechanically to the coal. 
The boillng was further continued after the gas-conducting tube had been 
placed over a graduated glass tube, previously filled with distilled water freed 
from air and placed on a pneumatic trough. The gas thus collected (con- 
stantly evolved from the lumps of coal) was analysed according to Bunsen’s 
method, and found to consist in the first sample operated upon of :—Carbonic 
acid, 16°9; marsh-gas, 20°43; nitrogen, 53°3; oxygen, 1°73; heavy carburetted 
hydrogens absorbable by fuming sulphuric acid 7°7 per cent. Second sample— 
Carbonic acid, 22°4; marsh-gas, 22°3; nitrogen, 48:0; oxygen, 471. The 
large quantity of nitrogen and the small quantity of oxygen deserve special 
notice. The samples of coal experimented with had been kept in a cellar for 
a period of several months in contaé with air so that it would appear that the 
oxygen of the air absorbed has served for the oxidation of the coal and forma- 
tion of carbonic acid. 
The presence of manganese has been shown by G. Campani to be a perma- 
nent constituent of blood. This subject was taken up by the author in conse- 
quence of a paper published in a scientific Italian periodical, wherein Dr. 
Pollacci asserts that manganese is an integral constituent of blood. It appears 
from the author’s experiments, made with blood of oxen, that the globules as 
well as the serum contain, along with iron, weighable quantities of manganese. 
As bearing somewhat on this subject, we may here record a very delicate test 
described by Dr. Béttger for the detection of minute traces of manganese. A 
few grammes of chemically-pure chlorate of potassa are first fused in a test- 
tube. and, while fused, there is put into it a minute quantity of the substance, 
mineral or organic, to be tested for manganese. If at the end of the reaction 
the contents of the thoroughly cooled tube exhibit a peach-blossom red 
colour, the substance thrown into the fusing chlorate of potassa contained 
manzanese, the presence of which may be thus ascertained in wood, human 
