426 Dr. Prout’s description of an acid principle 
colour becomes yellowish, but no precipitation takes place. 
Hence, this salt may be presumed to be very soluble. 
Purpurate of platina. The muriate of platina changes the 
colour of the purpurate of ammonia to a yellowish scarlet, 
but produces no precipitation. 
Purpurate of silver . Solutions of the acetate or nitrate of 
silver, dropped into a solution of the purpurate of ammonia, 
produce a deep purple precipitate ; and the water is left 
nearly colourless. Hence the purpurate of silver appears 
very insoluble. 
Purpurate of mercurf. A solution of the proto-nitrate of 
mercury produces, with the purpurate of ammonia, a beautiful 
reddish purple precipitate, and the water is left nearly 
colourless. A solution of the oxy muriate of mercury pro- 
duces at first no change ; but after some time a copious light 
rose coloured precipitate occurs, and the solution is left 
colourless. 
Purpurate of lead. A solution of the nitrate of lead, dropped 
in a solution of the purpurate of ammonia, renders it of a 
rose red colour ; but no precipitation takes place. 
Purpurate of zinc. A solution of the acetate of zinc 
produces with the purpurate of ammonia, a solution and 
precipitate of a beautiful gold yellow colour; and a most 
brilliant iridescent pellicle, in which green and yellow pre- 
dominate, forms on the surface of the solution. 
Purpurate of tin. A solution of the muriate of tin changes 
the purpurate of ammonia to a scarlet ; but this rapidly dis- 
appears, and the solution becomes colourless. After a few 
hours, white pearly crystals form in abundance, which is the 
purpurate of tin. 
