154 Mr. Faraday on the mutual action of sulphuric acid 
when 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 
water, soluble in alcohol, the solutions yielding imperfect 
crystalline 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 flame, 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 mode- 
rately 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. 
Manganese. The protoxide of this metal formed a neutral 
crystalline salt with the acid. It had a slightly austere taste. 
