140 Chemistry and Chemical Arts. 
powder, which is the tellurate of potash, containing modification A, 
and which is insoluble in the acids, and in the alkalies. In heating 
very powerfully in order to expel all the acid of the nitre and wash- 
ing, there remains another salt of the modification A, but more ba- 
sic, although insoluble. This salt, strongly calcined, is converted into 
a double tellurate, soluble in water. 
Tellurious acid is composed of one atom of tellurium and two at- 
oms of oxygen. 
Telluric acid contains: 
Tellurium, 920). 93.0 0P"O.7272==Iatom 
Oxygen; )) 9.02) 2.7.) 0.27283 atoms: 
In its crystallized hydrate there are three atoms of water.—Ann. 
des Mines, t. v. p. 381. 
15. Hydrate of Phosphorus. (Ann. de Pos., t. 27, p. 563.)— 
Phosphorus (says Rose) which has become white and opaque from 
having long been kept under water, is not an hydrate. After having 
been dried by sulphuric acid, it melts without any loss of weight or 
disengagement of water.—Idem. 
16. Phosphuret of Nitrogen, by Ross. (Ann. de Pog., t. 28, 
p- 529.)—By delivering gradually, ammoniacal gas ina state of dry- 
ness upon the proto-chloride of phosphorus, contained in a tube sur- 
rounded by a freezing mixture, an ammoniacal chloride is formed. 
This compound is white; it dissolves slowly in water, and is con- 
verted into a mixture of phosphite and hydrochlorate of ammonia. 
By heating it away from the air in a glass tube, not liable to melt, 
and which is traversed by a current of carbonic acid, it is completely 
decomposed ; hydrochlorate of ammonia, phosphorus, ammonia and 
hydrogen gas, are disengaged, and there remains a compound of 
phosphorus and nitrogen, perfectly white, when the chloride em- 
ployed is perfectly dry, but brown and reddish when the chloride 
contains a little moisture. This compound is pulverulent, light, m- 
fusible, and fixed at a red heat. With the contact of moist air, it 
produces abundant vapors of phosphoric acid without burning. It 
is remarkable for its chemical indifference, being insoluble in water, 
in nearly all the acids and in the concentrated alkaline solutions. It 
is not attacked by sulphur, chlorme, or hydrochloric acid gas; the 
alkaline hydrates decompose it in the dry way, with the production 
of phosphoric acid and the disengagement of ammonia; at a red 
