108 Analysis of Limestone. 



this method perfectly to keep separate the carbonats of 

 these two earths. 



31y. Throw down the carbonat of lime by carbonat 

 of ammonia : filter : then add to the muriat of magne- 

 sia containing carbonat of ammonia, phosphat of soda. 

 The ammoniaco-phosphat of magnesia is precipitated ; 

 and 151 grains of this triple salt dried at 90° of Fah- 

 renheit, answers to 100 grains of muriat of magnesia. 

 Hence, if 20 grains of a mixed solution of the muriats 

 of lime and magnesia give 15,1 grains of ammoniaco- 

 phosphat of magnesia, the mixture contains equal 

 quantities of muriat of lime and magnesia. Or, 100 

 grains so dried are equal to 111 grains chrystaliized, 

 or 62,2 of dried sulphat of magnesia. But this seems 

 to me below the average w^ater of chrystallization in 

 sulphat of magnesia, which contains nearly 50 per cent. 

 26 Nich. Journ. 277. 



This process, is used by Dr. Henry, Dr. Wollaston, 

 and I believe by Dr. Marcet. 



41y. The lime may be precipitated by oxalat of pot- 

 ash, and the muriat of magnesia, may be separated ei- 

 ther by the filter or by alcohol ; and precipitated either 

 by hot carbonat of potash, or by ammoniaco-phosphat 

 of soda. Or the alcohol or the acid may be driven off 

 by exposure for an hour to red heat. Or, by sulphu- 

 ric acid, the magnesia may be chrystaliized under gen- 

 tle evaporation into Epsom, or the bitter purging salt 

 of magnesia. 



51y. The muriat of lime, may be precipitated into 

 Gypsum, either by sulphuric acid, or by Glauber's or 

 Epsom salt, acidulated with a few drops of oil of vi- 

 triol. 



