64 The Art of Dyeing. 



3*37 grains. Again 500 grains were treated in the same 

 manner ; the remainder amounted to 1*68. Now 1*68 x 2= 

 3*37, precisely the same result as in the first trial. 



2. 1000 grains of the water afforded by means of nitrate 

 of silver '418 grains chlorine. 



3. A similar quantity yielded 2.07 grains sulphate of 

 barytes= '4028 grains sulphuric acid. 



4. To a third portion oxalate of ammonia was added, by 

 which means the lime was precipitated. It amounted to 

 •964 grains carbonate of lime, or -269 grains oxide. 



6 To obtain the magnesia and soda 1000 grains were 

 weighed out. The lime was precipitated by oxalate of am- 

 monia. The liquid separated from the precipitate was placed 

 in a platinum capsule and reduced to dryness. A few drops 

 of sulphuric acid were added to convert the magnesia and 

 soda into soluble sulphates, which were evaporated to 

 dryness, and heated carefully to redness in order to drive off 

 the excess of acid. The weight amounted to 1-3 grains. 

 This residuum was then dissolved in water, the magnesia 

 precipitated by boiling with carbonate of soda. This car- 

 bonate when heated gave '5028 magnesia. The soda, there- 

 fore, amounted to 0*0100 grains. 



The iron being held in solution by carbonic acid was 

 all precipitated before the water reached me, so that I was 

 unable to estimate its quantity. The proportion, however, 

 precipitated was not considerable. 



According to this analysis the solid contents in the im- 

 perial gallon are, 



Sulphate of magnesia . . 105*94 

 Sulphate of lime . . . . 47*64 

 Chloride of calcium . . . 38*00 

 Common salt 7*23 



198*81 



Article X. 



The Art of Dyeing. 



{Continued from vol. iii. page 455.) 



YELLOW FROM QUERCITRON AND ALUM MORDANT. 



To obtain a light quercitron-yellow, the calico is mordanted 

 in the manner described under berry-yellow. The same 



