COMBINATIONS OF OXIMURIATIC AGID AND METALS. 1^21 



sidue is oxide of manganese, white at first, but soon becoming 

 red, and even black ; it varies in quantity, according to the 

 exclusion of air in the formation of the combination. 



50 grains of the compound dissolved in water, with the es- Analysis. 

 ception of 1 grain ; this residue was separated by decantation 

 of the fluid, washed, dried, and heated to redness, it was in 

 the state of black oxide. The colourless solution was preci- 

 pitated by nitrate of silver. The horn silver formed, when 

 dried, was equal to 108 grains. Hence, omitting the 1 grain 

 of mixed oxide^ 100 of this compound appear to consist of 



54 chlorine 



46 manganese 



100 

 The horn lead, that I have analysed, was made by the de- Horn lead, 

 composition of the nitrate of lead by muriatic acid, and it was 

 well washed, dried, and fused in a glass tube with a small 

 orifice. The strongest red heat that I could apply to it, under 

 these circumstances, did not occasion its sublimation. 



50 grains of it, that had been fused, were dissolved in water. Analysis. 

 This solution, heated with nitrate of silver, afforded 52*65 grains 

 of dry horn silver. Hence 100 of horn lead appear to be com- 

 posed of 



25'7S chlorine 

 74-22 lead 



10000 



As this compoand, when decomposed by an alkali, affords 

 the protoxide of lead, it may be called plumbane. 



The butter of zinc I have examined was obtained by eva- Butter of nine, 

 porating to dryness the muriate of this metal, and by heating 

 to redness the residue in a glass tube. This compound is not 

 volatile at a strong red heat in a close vessel, it fuses before 

 it acquires a dull red heat, and on cooling it goes through 

 several degrees of consistence, being viscid before it.becomes 

 solid. 



This compound, when heated with water, affords a small 

 residue of oxide of zinc, which, as in the preceding instances, 

 may be considered as in the state of mechanical mixture. 



In consequence of its powerful attraction for water, it is a 



very 



