Value of Artificial Manures. 543. 
We have here 751/. 10s. as the cost of 100 tons of the manure ; 
by striking; off the two last figures in tlie division of pounds 
sterling (thus 7,51/.), we have 7^*5/., or 71. 10s. as the value of 
the manure. 
I can confidently recommend this method of " appraising " 
manures, as affording a rapid and easy result. As it deals with 
large quantities which are subsequently reduced to one-hundredth 
of the amount, minute calculations may be avoided, and the 
result will still exliibit only a slight discrepancy which is prac- 
tically unimportant. Thus in the last instance soluble phosphate 
was taken at 33/. per ton instead of 32/. 13s. Ad. ; the difference, 
65. Sd., multiplied by IG^ times, would amount to 5/. Os. 6d. on 
100 tons of the manure, or about Is. per ton, which of couise is 
quite within the limits of error. 
A class of manures has lately been introduced under the 
names of " Nitrophosphates, ' or " Ammoniacal superphos- 
phates," by which names it is intended to indicate a mixed 
manure, containing a larger proportion of nitrogen (or ammonia), 
and generally a smaller percentage of soluble phosphate than is 
to be met with in oidinary superphosphates. For the sake of 
illustration we may calculate the value of such a substance by 
reference to the Table. 
Thus, taking sample 51 in the list of superphosphates at 
page 549, we obtain the following results in 100 tons : — 
For 100 Tons. 
Moisture .. .. 8'90 per cent. £. s. 
Organic Matter, &c. 19" 72 ,, at IZ. per ton 19 15 
Insoluble Matter 
Soluble Phosphate 9- 63 at 33/. 
Insoluble Phosphate 13-37 ,, at 7/. 
Sulphate of Lime .. o9'77 at 1/. 
Alkaline Salts .. 4-8 at 1/. 
Ammonia .. .. 3* 88 ,, at 5GZ. 
319 0 
93 10 
40 0 
4 16 
218 0 
G95 1 
or, as nearly as may be, 11. per ton. 
Here we find that a larger percentage of ammonia and a 
smaller proportion of soluble phosphate are made to balance 
each other, so that the value of the manure remains about the 
same. 
On the other hand, if we select from the list of superphos- 
phates what would by the maker be emphatically called a " Nitro " 
or " Ammonia" phosphate, we sliall find a higher value for it; 
thus ]\'o. 56 in the list would give us the following results for 
100 tons :— 
2 N 2 
