206 On the Muriate of Tin. 



simple distillation in this manner, the vapours of muriatic 

 acid are very easily condensed and combined. 



If we direct vapours of oxygenized muriatic acid into a 

 vessel containing tin and common muriatic acid, the so- 

 lution takes place perfectly, and in a short time. The acid 

 at 20° then takes up one third of its weight in tin. 



I tried various mixtures of muriatic acid and nitric acid, 

 from one- sixth part of the latter up to one-tenth ; all of 

 them acted on the tin with extreme heat and violence, the 

 substances being forcibly ejected from the vessel. One part 

 of nitric acid, or the aqua fortis of commerce, at 35° of 

 Baume's areometer, and twelve parts of common muriatic 

 acid, at 20°, form a mixture very well adapted for the so- 

 lution of tin, which is thereby operated in a very short 

 time. This acid when mixed takes up about one-third of its 

 weight of tin, and the solution extends to the 45th degree. 



I tried to make the action of the muriatic acid, and that 

 of the atmospheric air, alternately concur on tin divided into 

 small pieces, in operating its solution, and I succeeded com- 

 pletely. For this purpose I filled a large glass saucer with 

 the tin, and covered it with muriatic acid at 20° for a few 

 hours ; I then poured the acid into another vessel, and it had 

 already ascended to the 25th degree. The tin becomes black 

 the moment it comes in contact with the air. There is an 

 absorption of atmospheric oxygen gas, an extrication of ca- 

 loric, which renders the metal very hot, and a lighted candle 

 when plunged into the saucer is speedily extinguished. As 

 soon as the vessel began to cool, I replaced the acid, which 

 acted with new vigour, and in a short time was as high as 

 35°. I withdrew it again, in order to give the action of the 

 air to the tin, and I rtplaced^it in the same manner, that it 

 might once more act. I repeated this operation from time 

 to time until the action ceased. In two days the solution 

 was at 45°, which it would attain e,ven in one day if we em- 

 ployed a series of saucers filled with tin: while the acid acts 

 upon some of the vessels, the air acts on the rest, and thus 

 the operation is never interrupted. 



The muriatic solution of tin, when recent, combines 

 speedily with oxygen gas from the atmosphere, as Messrs. 

 Pelletier, Guyton Morveau, and other celebrated chemists 

 have observed. It is sufficient to turn upside down a bell- 

 glass, full of atmospheric air, on a capsule or saucer filled 

 with this liquor, in order to see the latter ascend Into the 

 bell-glass until all the oxygen be absorbed. The absorption 

 is still more rapid, and becomes almost total in a short time/ 



when 



