Chemistry and Physics. 423 
place, and we may therefore add fluorine to the number of elements 
ince making these experiments, my attention has been directed to 
a note by the Messrs. Rogers, on the occurrence of fluor spar in an- 
thracite; these gentlemen correctly attribute the fluorine to the vegeta- 
tion of the coal plants, although no attempt seems to have been made 
to determine its constant presence in the coal. 
A single trial has shown that phosphoric acid is likewise present. 
have not repeated the experiment, but there can be no doubt that this 
constituent of plants of our era, was equally abundant in the coal plants. 
t be remarked, that the sulphur is not altogether found as sul- 
phuric acid in the sublimate, for hydrochloric acid disengages a large 
quantity of sulphurous acid. The investigation of this curious sub- 
stance is not yet completed. The results, if worth recording, will be 
communicated to this Journal. 
. Arseniate of Magnesia and Ammonia, and its applications ; by 
M. Levor, (Com.Rend., July, 1846; Ann. de Chim. et de Phys., Aug., 
1846.)—This salt is said to correspond in all respects with the phosphate 
of magnesia and ammonia ; it is formed in the same way and possesses 
the same sparing solubility in water containing ammonia. The presence 
of one part of arsenic acid in 18 of ammoniacal water was rendered 
evident on the addition of a strong solution of ammoniacal sulphate of 
magnesia. M. Levol proposes this salt as a means of estimating ar- 
senic acid when arsenious acid is present. The dried precipitate must 
be heated to a red heat, care being taken to avoid reduction of the acid, 
there remains 2MgO, AsO,. The insolubility of this salt renders it 
probable that the ammoniaco-magnesian salts will prove antidotes in 
cases of poisoning with arsenic acid. » QiBers 
3. On the Acids of Tobacco; by M. E. Gover, (Com. Rend., July, 
1846; Ann. de Chim. et de Phys., Aug., 1846.)—The chief organic acid 
of the tobacco is the malic. Bimalate of ammonia may be obtained 
readily from the plant, which in its dry state affords 3 to 4 per cent. 
M. Goupil has discovered that the conversion of the precipitated malate 
lead into a crystalline mass does not take place unless there is free 
acid present. This is an important fact, as the conversion into crystals 
is commonly assigned as a distinguishing character. 
Citric acid is found in the tobacco plant but in a very small quantity. 
No other organic acids could be found. -C.S, 
4. On the Fusion of Phosphorus; by M. Ep, Desains, (Comptes 
Rendus, July, 1846.)—The melting point of phosphorus, det d 
14°. The phosp 
. 
tion it may remain liquid even at 72°; on solidifying, its temperature 
104 
for the two different states of the substance. 
5. On Coffee, (third part ;) by M. Payen.—In order to isolate the 
aromatic substance of the coffee, the usval hot infusion was distilled in 
~ & vessel connected: with several successive receivers kept at different 
ratures, The aromatic principle was found almost entirely con- 
in that which had preserved a temperature of about 80°. Sey- 
