BARIUM. 
§ 939-94 1 -] 
725 
According to Kowalewsky , 1 the acetate of uranium possesses an unusual power 
of uniting with albumin ; the other soluble uranium salts act also in a similar way. 
Hence concentrated solutions of uranium salts corrode the mucous membranes, trans¬ 
forming, for example, the walls of the stomach into a dead uranic albuminate. If a 
non-corrosive salt of uranium is injected subcutaneously, glycosuria is produced, with 
fatty degeneration of the walls of the blood-vessels, and fatty changes in the kidneys, 
liver, etc. The animal wastes and ultimately dies. 0-5 to 20 mgrms. of U0 3 per 
kilogrm. will kill a cat, dog, or rabbit, if injected subcutaneously. The nitrate or 
acetate, when given by the mouth, produces gastro-enteritis and nephritis, with 
haemorrhages in the substance of the kidney. Uranium is not used in medicine. 
§ 939. Detection and Estimation of Uranium. —Uranium forms uranous and 
uranic salts. Both classes of salts are not precipitated by SH 2 , but are precipitable 
by ammonium sulphide, and, therefore, in toxicological analyses are likely to be met 
with in conjunction with iron. 
The sulphides of iron and uranium may be dissolved in strong hydrochloric acid, 
boiled to expel SH 2 , and the solution then oxidised with a little nitric acid ; the solu¬ 
tion is now alkalised with ammonium carbonate, which precipitates the iron as oxide 
and leaves the uranium in solution. On now acidifying with nitric acid in slight 
excess, a solution of sodic phosphate will precipitate uranium phosphate as a white 
precipitate, alkalies will give a yellow precipitate, alkaline carbonates a yellow pre¬ 
cipitate soluble in excess. Barium carbonate also gives a precipitate, and is useful 
in separations. Uranium oxide gives a green glass in the oxidising flame with borax 
or with sodic metaphosphate. 
V.—ALKALINE EARTHS. 
Barium. 
§ 940. The soluble salts of barium are undoubtedly poisonous, and- 
are of frequent occurrence in the arts. The chloride of barium is used 
in the staining of wool, the nitrate and the chlorate in the green fires of 
the pyrotechnist, the oxide and the carbonate in the manufacture of 
glass. The chromate is used by artists under the name of “ yellow 
ultramarine,” while the sulphate, technically known as “ permanent 
white,” is, on account of its weight and cheapness, occasionally used as 
an adulterant of white powders and other substances. Barium sulphide, 
under various names, such as Bottcher’s depilatory, Thompson’s hair 
destroyer, Poudre epilatoire, and other names, is in commerce, and has 
caused poisonous symptoms. 2 
§ 941. Chloride of Barium, BaCl 2 2H 2 O = 208+36—anhydrous, Ba, 
65-86 per cent. ; Cl, 34-14 ; specific gravity, 3-75—is in commerce in the 
form of white, four-sided, tabular crystals ; water dissolves about half its 
weight at ordinary temperatures, three-fourths at 100°. Its solution 
gives a white precipitate with sulphuric acid, quite insoluble in water 
and nitric acid. 
The salt imparts a green hue to an otherwise colourless flame ; 
viewed by the spectroscope, green bands will be visible. We may 
note that chloride of barium gives two different spectra—the one at 
1 Zeit. f. anal. Chemie, xxiv. 551, 1885. 
2 Barium carbonate and sulphate arc usually enumerated as occasional adul¬ 
terants of bread, but there is no modem authentic instance of this. 
