62 Messrs. Merck and Galloway's Analysis of 



I. 765*325 grms. of water gave 0*7211 grra. of carbonate 

 of lime = 0*4038I6 grm., or 0*05276 per cent, of lime. 



II. 732*015 grms. of water gave 0*6981 grm. of carbonate 

 of lime = 0*3909 grm., or 0*05340 per cent, of lime. 



Mean of the results, 0*05308 per cent. 

 Mean of the lime combined with carbonic acid 0*00706 

 Mean of the lime combined with sulphuric acid 0'04709 

 Total amount found by addition 0*05415 

 Mean of the total amount found by direct ^sti-l ^ „^^^q 

 mation j 



6. Estimation of Magnesia. 



The estimation of the magnesia was divided in the same 

 manner as the estimation of lime into — 



A. Estimation of the magnesia combined with carbonic 

 acid. 



B. Estimation of the magnesium combined with chlorine. 



C. Estimation of the total amount of magnesia for control. 



A. Estimation of magnesia contained in the water as car- 

 bonate : — 



To the liquid filtered off from the oxalate of lime was 

 added phosphate of soda ; on stirring, after some time a pre- 

 cipitate of phosphate of magnesia and ammonia was formed, 

 which was converted by ignition into pyrophosphate of mag- 

 nesia. 



I. 777*215 grms. of water gave, on boiling, a precipitate 

 which contained 0*0046 grm. of pyrophosphate of magnesia 

 = 0*001685 grm., or 0*00021 per cent, of magnesia. 



II. 623*881 grms. of water gave, on boiling, a precipitate 

 which contained 0*0044 grm. of pyrophosphate of magnesia 

 = 0*00016 grm., or 0*00025 per cent, of magnesia. 



Mean of the results, 0*00023 per cent. 



B. Estimation of the magnesia contained in the water as 

 chloride of magnesium. 



The liquid filtered off from the oxalate of lime was con- 

 centrated by evaporation, ammonia added filtered off from a 

 small portion of silicic acid which separated, and the mag- 

 nesia precipitated by phosphate of soda. 



I. 414*279 grms. of water gave in this way 0*1007 grm. 

 of p3'rophosphate of magnesia = 0*03689 grm., or 0*008906 

 per cent, of magnesia. 



II. 427*1 grms. of water gave 0*1050 grm. of pyrophos- 

 phate of magnesia = 0*03846 grm., or 0*009004 per cent, of 

 magnesia. 



Mean of the results, 0*008955 per cent. 



