ON SILVER. 379 



occasions no cliange ; the minimum deprives it entirely 

 of colour, and the silver is reduced. 



The tincture of fecula of hemlock, which is of a tincture of 

 feuillemort colour, is not changed by the maximum ni- "C^^o*^!^ 

 trat : by the minimum the green is revived and beautified 

 in a striking manner. 



JVUh Ammonia, 

 Ammonia precipitates the minimum nitrat black. The ammonia, 

 precipitate collected is pure silver, and does not fulmi- 

 nate, howevfer long it be kept in the ammonia. The 

 ammonia then holds «2«A?/mww oxide in solution; for if 

 it be saturated with very dilute nitricacid, it is no longer 

 blackened by ammonia. Thus we see, that the portion 

 6f oxide dissolved in ammonia is raised to a maximum at 

 ihe expense of that which is precipitated. 



With pure Potash, 

 • The precipitate is brown, resembling in colour that pota»h, 

 giveti by the maximum nitrat, Redissolred in nitric 

 ac^d, ammonia precipitates it black, which demonstrates 

 Inat the oxide has not altered its state ; but on drying it 

 a< tracts oxigen from the atmosphere, rises to the -Tnaxi-. 

 mitm^' afid no longer differs from the precipitate afforded 

 hf4\{t mttximumwiiviLi, 



With AkolioL 

 Alcohol acts on its solution no otherwise than water: ^^Qij<,j 

 part of the nitrat, its portion of acid being diminished, 

 sepkrates in a yellow powder. The alcoholic solation , ^^ 



being distilled, leaves 'behind nitrat at 3, maximum and ' '-'■^■, 



powder of silver, because part of the oxide has completed 

 its oxidation at the expense of the other. The alcohol 

 is not converted into ether in this case, any more than 

 with i^e- maximum nitrat, which it dissolves perfectly 

 wdl. ' ' 



With boiling Water, 

 It has been seen, that cold water separates thi^- nitrat and boiling 

 in'to two parts ; that one, to enable it to dissolve, was water, 

 ♦bliged to take acid from the other^ which was <;o»se* 



quently 



