Neutral Salts. 289 



2. Pass sulphureous acid gas through a solution of caustic 

 soda. Used to bleach straw hats. 



Acetate of soda, Soda acctata. Saturate acetic acid with 

 ubcarbonate of soda, filter, evaporate, and crystallize ; milder to 

 he taste than acetate of potash. 



Arse XI ATE of soda, Arscnias sodcB. White arsenic 9oz., 

 drj' nitrate of soda Ib'oz. ; mix and heat together in a bolt head 

 or a sandbath, until the nitric acid is dissipated ; dose one-sixth 

 of a grain. 



Nitrate of soda, XUras sodce. Saturate a solution of sub- 

 carbonate of soda with nitric acid, evaporate and crystallize. 

 Used to prepare arseniate of soda. 



Subphosphate of soda. Saturate a solution of subcarb. 

 of soda with liquid phosphoric acid, evaporate, and crystallize. 

 Used as a test in blowpipe experiments, and also dissolved to 

 discover silver in saline solutions. 



Tasteless purging salt. Soda phosphata, Phosplias sodce. 

 Dissolve phosphoric acid in water, add subcarb. of soda q. s. to 

 saturate the acid : evaporate and crystallize. 



2. Dissolve well-burnt bones in nitric acid ; dissolve also 

 Glauber's salt in water, and pour it into the nitrous solution, as 

 long as a precipitation takes place ; filter, and distil the liquor to 

 recover the nitric acid, wash, evaporate and crystallize ; purgative 

 3vj to 3x, in broth : used also to prepare cobalt blue. 



Glauber's salt, Sulphate of soda^ Sal inirabilis Glauberi, S, 

 ratharticus Gkndjeri, Natron vitriolatum, Sodcc sidpJias. Dissolve 

 ihe residuum left in distilling sulphuric acid upon salt, in water, 

 saturate the excess of acid, either with subcarb. of soda, or pow- 

 dered chalk ; filter, evaporate and crystallize. 



2. To common spirit of bones or ammoniacal liquor add oil of 

 vitriol, crystallize the sulphate of ammonia thus made, mix this 

 with common salt, sublime the sal ammoniac from it, and the 

 Glauber's salt remains, which is to be dissolved and crystallized. 



Lymingtox Glauber's salt, Sulphate of magnesia and soda. 

 Obtained from the mother liquor of sea water, crystallizing in 

 rhomboids. 



2. By dissolving Epsom salt in a solution of Glauber's salt. 



H'" H! lle salt, Sal Ifi/prllensisy Natron tarfarisnfnm, Soda 



fin f.!, iMitd^ 'J'ortriH potassa; ft .sod<^, 7'artras votassat ct sodce, 



\) ulve sulnarb. of soda 20 oz. in water 101b.; add, while 



tHj:iing, cream of tartar 21 oz. : filter, evaporate to a pellicle, and 



rystalhze. 



