“ 
aed 
4 
Behe. 3 
Bsenay. by” S 
New York AagricutturaL Experiment StarIoNn. 199 
Now to this may be added 485.6 pounds of gypsum and we 
would have 2,000 pounds of the mixture of the required compo- 
sition. 
It will be observed in this mixture there are in all but 14.65 
per cent of nitrogen, phosphoric acid and potash, and not infre- 
quently the suspicion arises that the remaining 85.35 per cent is 
used by the manufacturer in the nature of a filler, but if we 
examine the material which we have used in the preparation of 
this fertilizer we shall see that this is an erroneous view and very 
unjust to the manufacturer, for to secure our needed amounts of 
hitrogen, potash and phosphoric acid we used as follows: 


Pounds. ‘ Pounds. 
64.8 | Sulphate of ammonia containing only} 13.3 | Nitrogen. 
80.6 | Nitrate of soda containing only.... 13.3 | Nitrogen. 
126.2 | Dried blood containing only ...... 13.3 | Nitrogen. 
127.8 | Muriate of potash containing only . 67.1 | Potash. 
1115.0 | Dissolved bone black contain’g only} 186.2 | Phos, acid, 
1514.4 | 293.2 
- 485.6 | Plaster or gypsum. 
2000.0 
— 
To obtain, therefore, the desired amounts of these three fertil- 
izing constituents we have had to introduce 1221.2 pounds, about 
eighty-one per cent of other matter. The plaster added to make 
up the round ton might properly be regarded as a filler. 
In the preparation of superphosphate of lime from bone ash, 
two-thirds of the lime combined with the phosphoric acid is taken 
away by the sulphuric acid which is added to the bone ash, and 
the sulphuric acid and lime unite to form sulphate lime or plaster 
or gypsum. 
In a complete reaction 138 parts by weight of bone ash 
ninety-eighty parts of sulphuric acid would form 117 parts by 
weight of superphosphate of lime and 120 parts of sulphate of 
lime, but this 117 parts of superphosphate would contain seventy- 
one parts of sulphuric acid, so, as will be seen, in order to get 
this seventy-one parts of phosphoric acid it is necessary 
