458 ANALYSIS OF THE 



the solution of the sohd matter which had been procured by 

 evaporation, and care being taken that the ammonia was free 

 from carbonic acid, little or no precipitation could take place 

 but of oxide of iron. A yellowish flocculent precipitate sub- 

 sided slowly, which, after being washed, was added to the inso- 

 luble residue. 



The insoluble matter thus collected consisted, as the prece- 

 ding steps of the analysis establish, chiefly of sulphate, with a 

 smaller portion of carbonate of lime, with which was mixed the 

 oxide of iron. A drop or two of sulphuric acid was added, to 

 convert the carbonate into sulphate of lime ; and heat was ap- 

 plied to expel any excess of acid. A little pure muriatic acid 

 was then added to dissolve the oxide of iron, and to form with 

 more certainty the red muriate, soluble in alkohol, a drop of 

 nitric acid was added along with it. On applying heat, with 

 the addition of a little water, to favour the action, a yellow co- 

 lour was acquired. When the excess of acid was nearly dissipa- 

 ted, the mass was repeatedly lixiviated with alkohol, in which 

 sulphate of lime being insoluble, the muriate of iron only 

 would be dissolved. The alkohol acquired accordingly a yel- 

 low colour. Being evaporated by a gentle heat, it gave a resi- 

 duum which, on a drop of nitrous acid being added, became 

 of a deep reddish-brown colour, and after being heated strong- 

 ly weighed 0.34 grain. Re-dissolved in muriatic acid, it form- 

 ed a rich yellow coloured solution, and gave a deep colour with 

 tincture of galls. 



Even in this way, the whole iron is not obtained ; for the so- 

 lution of the saline matter, though ammonia had been added 

 to it, to precipitate the iron, still gave a weak colour with galls.. 

 The quantity therefore is rather under-rated. Taking the 

 above, however, as the proportion, the whole composition will 

 be in a pint of the water of the North Spring, 



Muriate 



