178 Fuming Liquor of Libavius. [Book VI. 



formed needles, which flightly attract the humidity 

 of the air. The oxygenated muriatic acid diflblves 

 tin very readily, and without the leaft fenfible effer- 

 vefcence. Aqua regia, confifting of two parts nitrous 

 and one muriatic acid, combines with tin with effer- 

 vefcence and the developement of much heat. The 

 foiution of tin in aqua regia is ufed by dyers to 

 heighten the colours of cochineal, gum lac, and fome 

 other red tinctures, from crimfon to a bright fcarlet, 

 in the dying of woollens. By firft diffolving tin in the 

 marine acid, and then boiling the foiution with nitrous 

 acid diftilled from manganefe, M. Hermfta=ut has 

 fucceeded in acidifying tin to fuch a degree as to con- 

 vert it into an acid ; it had then the form of a white 

 powder, foluble in three times its weight of water. 



Tin has a ftronger affinity with the muriatic acid 

 than mercury has, and decompofes the corrofive mer- 

 curial fublimate. To effect this, the tin is firft di- 

 vided by the addition of a fmall portion of mercury ; 

 equal parts of this amalgam and the corrofive fubli- 

 mate are triturated together, and the mixture expofed 

 to diftillation in' a glafs retort with a very gentle heat. 

 A colourlefs liquor firft paffes over, and is followed 

 by a thick white vapour. The vapour becomes con- 

 denfed into a tranfparent fluid, which continually emits, 

 a thick, white, and very abundant fume. It is called 

 the fuming liquor of Libavios, and is a combination 

 of the muriatic acid and tin. The fmell of this flu-id 

 is very penetrating, and excites coughing. The va- 

 pours are not vifible without contact of air, and fecm 

 to confift of a peculiar gas, which is dccompofable by 

 air, and which then depofits the calx of tin in the 

 fame manner as the hepatic gas of Bergman depofits- 

 fulphur by the contact of air. M. Fourcroy pro- 

 .- it as a query, whether this elaftic fluid is a 



compofition, 



