54 
SOI)II PHOSPHAS EFFERYESCEXS. 
Effervescent Sodium Phosphate. 
• 
A similar compound is official under the same name in the British 
Pharmacopoeia. 
It is composed of the Exsiccated Sodium Phosphate, Sodium Bicar- 
bonate, and Tartaric and Citric acids. It contains just sufficient 
sodium bicarbonate to neutralize the tartaric and citric acids when it 
is dissolved in water, and the carbonic acid gas liberated gives a pleas- 
ant acidulous and effervescent taste. 
Dose. — “Average dose: 8 Gm. (120 grains).*' (U. S. P.) 
It should be kept in well stoppered bottles. 
SODII PHOSPHAS EXSICCATES. 
Exsiccated Sodium Phosphate. 
Xa,HPO, 
This is also called anhydrous sodium phosphate; it is obtained by 
driving off the water of crystallization of Sodium Phosphate (U. S. P.), 
which amounts to 60.3 per cent of the latter's weight. In a given 
weight of the exsiccated salt there are two and a half times as much 
sodium phosphate as in the same weight of the crystallized salt. 
It is a white powder which absorbs moisture readily when exposed 
to the air and is gradually transformed into a salt of the composition 
Isa. 2 HPO i + 7H.,0, which contains about 47 per cent of water; the 
latter salt is permanent. 
Dose. — “Average dose: 1 Gm. (15 grains)." (U. S. P.) 
STROXTII SALICYLAS. 
Strontium Salicylate. 
Sr(C 7 H 5 0 3 ) 2 + 2H 2 0 
Character. — White, crystalline powder, odorless and having a sweet- 
ish saline taste. 
Solubility. — Soluble in water (1:18) and alcohol (1:66), much more so 
when these are boiling. 
Incompatibility. — Incompatible with ferric salts, mineral acids, qui 
nine salts in solution, spirit of nitrous ether, and sodium phosphate 
in powder. 
Dose. — “Average dose: 1 Gm. (15 grains)." (U. S. P.) 
Keep in well stoppered bottles, protected from heat and light. 
Strontium Lactate (U. S. P., 1890) has been dismissed from the 
Pharmacopoeia; the bromide and iodide are retained. 
