355 
usually free from even traces of iron. He also believes that the Ph. 
Germ, test for lime salts should be made less rigorous. — Pharm. Ztg. 
Berl., 1906, v. 51, p. 1004. 
Ehman, J. W., reports that G. S. Dubois examined six samples of 
official magnesium carbonate and found, loss on ignition ranging from 
38.15 per cent to 45.2 per cent, average 41.77 per cent. Carbon dioxide 
ranging from 33.77 per cent, 37.2 per cent, average 35.89 per cent. 
The sample giving the smallest percentage of residue and carbon 
dioxide was most nearly free from impurities, showing onty a faint 
trace of iron. — Am. J. Pharm., Phila., 1906, v. 78, p. 416. 
Caspari, Chas. E., reports five samples examined; all contained 
metallic impurities. — Proc. Missouri Pharm. Ass., 1906, p. 99. 
Ohliger, Willard, found a sample of crude magnesium carbonate 
which contained an excess of iron and a trace of calcium and was 
soluble in dilute acids only on heating. — Proc. Michigan Pharm. Ass., 
1906, p. 48. 
Dieterich, Karl, reports the presence of an excess of chloride and 
sulphate in magnesium carbonate. — Helfenberger Annalen, 1905, 
1906, v. 18, p. 89. 
MAGNESII OXIDUM. 
The Ph. Brit. Committee of Reference in Pharmacy report on mag- 
nesia points out that some allowance should be made for loss on 
ignition (water and carbonic acid absorbed). — Chem. & Drug., Lond., 
1906, v. 69, p. 864. 
Grimbert proposes to replace the solution of hypoiodate of sodium, 
proposed by Schlagdenhaufen for the determination of magnesia, by 
the successive addition of iodide of potassium and hypochlorate of 
soda. The reaction is sensitive to 1 : 2,000 without valuing the pre- 
cipitation of magnesia in the form of ammonio-magnesian phos- 
phate. — J. de pharm. et de chim. Par., 1906, v. 23, pp. 237-239. 
Bellier, J., thinks that while Grimbert ’s modification is well enough 
in the presence of appreciable quantities of magnesium salts it is not 
as sensitive as the Schlagdenhaufen reaction where there are but 
traces present. — Ibid., v. 23, pp. 378-381. 
Dieterich, Karl, reports on three samples of magnesium oxide. 
Two samples contained carbonate, and all three contained sulphate 
and traces of iron. — Helfenberger Annalen, 1905, 1906, v. 18, p. 89. 
Philipp Roder, Wien, asserts that magnesium oxide free or nearly 
free from carbonate is difficult to obtain and suggests that the pharma- 
copoeia permit the presence of carbonate but direct a maximum 
content. — Pharm. Zentralh., 1906, v. 47, p. 522. 
Hankey, William T., has found it difficult to secure a sample of 
magnesium oxide that will gelatinize when one part is mixed with 
: 
,1 HKj 
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