MR. GEORGE GORE ON FLTJORIEE OF SILVER. 
237 
ammonia. The behaviour of argentic fluoride in a state of fusion in a current of dry 
gaseous ammonia has been already described (see p. 229). A saturated aqueous solution 
of argentic fluoride was instantly decomposed with powerful action by the strongest 
aqueous ammonia, but no precipitate was observed. 
With Oxygen. — 24'G grains of oxide of silver previously heated to 600° Fahr. was 
introduced into a platinum tube-retort containing 49‘86 grains of the previously fused 
salt, and 20 grains of platinum scraps, and the retort (enclosed in a test-tube) heated in a 
bath of melted zinc to an incipient red heat during fifteen minutes until evolution of gas 
ceased. The loss of weight was 1*8 grain, and about 5^ cubic inches of gas was collected 
over mercury. The gas was proved to be oxygen, and the residue contained soluble un- 
decomposed fluoride. Fluoride of silver therefore is not decomposed by heating with 
oxide of silver. A globe (see fig. 6) was filled with pure and dry oxygen. The platinum 
retort B, containing the residue of the last experiment, was fixed air-tight on the tubu- 
lure C, and the outer end of the retort heated to low redness during half an hour, the 
open neck of the receiver being immersed in mercury. No alteration of volume or pro- 
perties of the gas took place, and the loss of weight was only T6 grain. This result, 
therefore, confirms the previous one. The effect of dry air upon the salt in a state of 
fusion has been already described (see p. 234). 
With W iter . — The behaviour of the salt with liquid water has been already described 
(see p. 231). 20 grains of the brown salt was heated to fusion in a platinum boat within 
a glass tube, and a current of steam passed over it ; rapid decomposition took place ; the 
salt lost its fluidity and became of a brown colour for a short time, as if converted into 
oxide of silver ; abundance of hydrofluoric acid was set free and the glass corroded power- 
fully ; soon, however, by more heat the whole of the salt was changed into white silver. 
The loss of weight was 4‘45 grains, consisting no doubt of fluorine (united to hydrogen), 
substance carried away mechanically by the violence of the action, and a small amount 
of acid moisture originally contained in the brown salt. This confirms the results 
obtained by heating the salt to fusion in undried atmospheric air (see p. 233). 
With Nitrons Oxide . — 71 *6 4 grains of the recently fused salt in a platinum boat inside 
a platinum tube within a platinum tube-retort at a low red heat was subjected to a 
current of previously dried nitrous oxide during one hour. No chemical change took 
place, and the loss of weight was only *27 grain. Argentic fluoride, therefore, is not 
decomposed by nitrous oxide at a low red heat. 
With Nitric Oxide . — A current of dried nitric oxide from a mixture of nitre, sulphuric 
acid, water, and ferrous sulphate, was passed during forty-five minutes over 75 '2 grains 
of the previously fused salt in a platinum boat within a short platinum tube placed in 
the middle of another platinum tube 508 millims. long, the salt being kept at an inci- 
pient red heat. Traces only of hydrofluoric acid were set free, and the salt lost only 
•5 grain in weight; the loss might have been due to traces of moisture still remaining 
in the gas. Argentic fluoride, therefore, is not decomposed by nitric oxide at a low red 
heat. 
MDCCCLXX. 
2 i 
