210 Mr, Faradai/ on the Mutual Action of Sulphuric Acid [Sept. 



heated burnt with a bright flame, without any red tinge, and 

 left a result of the usual kind. 



Lime gave a white salt of a bitter taste, slightly soluble in 

 >*ater, soluble in alcohol, the solutions yielding imperfect crys- 

 talline-forms on evaporation : it burnt with flame ; and both in 

 the air and in tubes, when heated, gave results similar to those 

 of the former salts. 



Magnesia formed a white salt with a moderately bitter taste ; 

 crystallizing in favourable circumstances, burning with flume, 

 and giving such results by the action of heat as might be 

 expected. 



Iron. The metal was acted upon by the acid, hydrogen 

 being evolved. The moist protoxide being dissolved in the acid 

 gave a neutral salt capable of crystallization. This by exposure 

 to air slowly acquired oxygen, and a portion of per-salt was 

 found. 



Zinc was readily acted upon by the acid, hydrogen evolved, 

 and a salt formed. The same salt resulted from the action of the 

 acid upon the moist oxide. It was moderately soluble in hot 

 water, the solution on cooling affording an abundant crop of 

 acicular crystals. The salt was white, and unchangeable in the 

 air ; its taste bitter. It burnt with flame, and gave the usual 

 results by heat. 



Lead, The salt of this metal was white, solid, crystalline, 

 and soluble in water and alcohol. It had a bitter metallic taste, 

 with very little sweetness. The results by heat were such as 

 might be expected. 



Man^ajiese. The protoxide of this metal formed a neutral 

 crystalJme salt with the acid. It had a slightly austere taste, 

 was soluble in water and alcohol, and was decomposed by heat, 

 with the general appearances already described. 



Copper, Hydrated per-oxide of copper formed an acid-salt 

 with the acid, and the solution, evaporated in the air, left radiated 

 crystalline films. The dry salt, when heated, fused, burnt with 

 flame, and exhibited the usual appearances. 



Nickel. The salt of this metal was made from the moist 

 carbonate. It was soluble, crystalline, of a green colour, and 

 decomposed by heat in the usual manner. In one instance, an 

 insoluble sub-salt was formed. 



Silver, Moist carbonate of silver dissolved readily in the 

 acid, and a solution, almost neutral, was quickly obtained. It 

 was of a brown colour, and a powerful metallic taste. By eva- 

 poration it gave a splendent, white, crystalline salt ; not chang- 

 mg in the air except when heated ; but then, burning with flame, 

 and ultimately leaving pure silver. When the solution of the 

 salt was boiled for some time, a black insoluble matter was 

 thrown down, and a solution obtained, which, by evaporation, 

 gave abundance of a yellow crystalline salt. The changes 



