The Purchase of Artificial Manures. 



455 



Fish Meal, say 8 per cent, of nitrogen x us. gd. = £4 14s., 

 together with an allowance of about £1 for phosphates, 

 giving a total value of £5 14s. per ton. .Some samples of 

 fish meal hold more and some less than 8 per cent, of 

 nitrogen, in which case the value would rise or fall, though 

 not quite proportionately, on account of the phosphates. 



Blood Meal, say 12 per cent, of nitrogen x us. gd. = £y is., 

 together with about 5s. on account of a little phosphate. 



Rape Meal, say 5 per cent, of nitrogen x lis. gd. = 

 £2 1 8s. gd. per ton. 



The values per ton for these three manures are consid- 

 erably higher than the merits of the manures would warrant. 

 These manures, in fact, are only worthy of a farmer s atten-) 

 tion, under ordinary circumstances, when they can be bought 

 at a rate per unit of nitrogen that is considerably less 

 than that which applies to nitrate of soda or sulphate of 

 ammonia. 



Phosphatic manures are also valued in the same way. 

 At the present time the insoluble phosphates in basic slag 

 ■are valued at about is. 3d. per unit, and at this rate a sample 

 containing 40 per cent, may be put at 40 x is. 3d. = £2 10s. 

 per ton, carriage paid, while a 30 per cent, sample is no better 

 value at 37s. 6d. As a rule the lower grades cost more per 

 unit than the higher qualities, so that the latter are usually 

 the better value. 



The soluble phosphate of superphosphate may at present 

 valued at about is. gd. per unit. At this late a 28 per 

 cent, sample would cost £2 9?. per ton, carriage paid, while 

 -a 34 per cent, sample would be as good value at 

 £2 19s. 6d. 



In bone meal — which should only be bought when very 

 finely ground, really dust — the nitrogen is usually valued at 

 about the same rate as that in sulphate of ammonia, while 

 the phosphate may be put at the same rate as that 

 which prevails for basic slag. On this basis a sample con- 

 taining 4 per cent, nitrogen and 50 per cent, insoluble 

 phosphates would work out as follows, though it can often be 

 bought for less : 



