Soot Ammonia Gas-Liquor. 13 



therefore, to select a sample which on an analysis exhibits the 

 greatest amount of ammonia and the smallest of mineral or in- 

 combustible matters. The following determinations will show 

 that the proportion of ammonia in soot varies greatly in different 

 samples : 



100 Ibs. of soot, No. I., contained ammonia .. .. 1*872 Ibs. 

 No. II. .. .. 3-833 



No. III. .... 5-360,, 



In a rough manner the comparative value of different samples 

 of soot may be ascertained by mixing each with some quicklime 

 and a little water : that which gives off the most pungent smell 

 of ammonia will be the most valuable. 



Sulphate of Ammonia is now frequently used as a top-dressing 

 for grass, spring-wheat, and other crops, which are benefited by 

 ammoniacal matters. 



Occasionally it is adulterated with the cheap sulphate of soda 

 or glauber-salt. A table-spoonful heated on a shovel in the 

 grate should leave no residue, which is the case if it is adul- 

 terated with glauber-salt, or any other cheap fixed salt. 



Two different specimens, on analysis, were found to contain 

 in 100 parts : 



I. II. 



Moisture -11 2'17 



Fixed salts -11 3'08 



Sulphate of ammonia 99-88 94-75 



100-00 100-00 



No. I., it will be observed, was nearly pure sulphate, whils, 

 No. II. contained about 5 per cent, of impurities. Sulphate of 

 ammonia is sold at present at 187. per ton ; No. II. consequently 

 was worth 185. less than No. I. 



Ammoniacal Liquor of Gasworks. This refuse liquor of gas- 

 works contains carbonate of ammonia, a little sulphide of am- 

 monium, and traces of tarry matters, and owes its efficacy and 

 value solely to the carbonate of ammonia. 



In some localities it is a favourite manure with the farmers, 

 whilst in others it is hardly employed at all for manuring pur- 

 poses. At times of great demand, occasionally a stream of 

 pump-water is directed into the tank in which this liquor ac- 

 cumulates at the gasworks. As, moreover, the* amount of car- 

 bonate of ammonia naturally varies with the kind of coal em- 

 ployed in gasworks, it is necessary to ascertain the amount of 

 ammonia in the liquor, in order to obtain the data from which 

 its value may be calculated. 



Two specimens of ammoniacal liquor, obtained at different 



