ANALYTICAL ASSOCLITIONS. 401 



low feeding value. When valued according to the units appli- 

 cable to linseed cake, viz., 3s. 9d. per unit of albuminoid matter 

 and oil, and Is. per unit of carbohydrates, their value scarcely 

 reaches £7 per ton. Barley meal can be bought at about one- 

 third the price of these substances, so that the prices paid for 

 them is out of all proportion to their feeding value. 



Soot. — A sample of soot supplied to a member of the Kelso 

 Analytical Association was found to contain — 



Phosphates, . . . 0'78 per cent. 

 Ammonia, . . . 4*26 „ 



The composition of soot is apt to vary very much, as it 

 depends not only on the kind of coal which produced it, but also 

 and perhaps chiefly on the way in which the coal is burned. 

 The above represents a good kind of soot, somewhat above average, 

 although it fell considerably below its guarantee, which was 

 1*92 per cent, phosphates and 6'12 per cent, ammonia. A 

 guarantee of soot has to be received with caution, as from its 

 great variability throughout the bulk it is difficult to prepare in 

 such a way as to yield a representative sample. 



Pigeon Dung. — A member of the same association bought a 

 quantity of pigeon dung, whose composition was not guaranteed, 

 but which was found on analysis to contain — 



Phosphates, . . . 2*54 per cent. 

 Ammonia, . . . 1'21 „ 



The price paid for it was at the rate of £3, 10s. per ton, which 

 is more than double its value. The buyer may have thought, as 

 many would naturally enough think, that this kind of manure 

 would in some measure resemble an ammoniacal guano, such as 

 Ichaboe guano, which is a recently formed deposit. But the 

 character of the dung of birds is determined by the nature of 

 their food, and the food of granivorous birds, like pigeons, is very 

 different from that of the fish-eating birds to whom we owe the 

 guano deposits. This is just another instance of the disadvantage 

 of Ijuying a manure without an analytical guarantee. 



The number and variety of phosphatic materials offered to 

 farmers and manufacturers is very considerable, and has hitherto 

 been greater than in the case of other manurial substances. It 

 is gratifying to tind that the number of nitrogenous materials is 

 now rapidly increasing, and it is evident from the high prices 

 being paid for them that they are much appreciated. High class 

 Teruvian guano, the supjdy of which fell away so much lately, is 

 now being more freely imported. Those who are acquainted 

 with the extent of the guano deposits assure us that the day is 

 not far distant when the supply of that splendid manure will 

 cease, and we must therefore regard with interest every other 



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