198 THE VALUE OF NATIVE GUANO. 
can be no question as to the manner of tbeir propagation; 
having arisen,, they extend by virtue of the peculiar proper¬ 
ties which are acquired by the solids and fluids of the dis¬ 
eased animal’s body. If the germs of the disease are so 
minute that they can be carried in the air, then diffusion is 
all the more certain and extensive; if they are of grosser 
material, they must be conveyed from the diseased to the 
healthy animal in some more palpable way; but in whatever 
way the transference takes place, the fact remains that all 
contagious and infectious diseases spread only when the 
germs of the disease are in some way conveyed from an 
infected animal. 
Extracts from British and Foreign Journals. 
THE VALUE OF “ NATIVE GUANO.” 
The Reports just tendered to the Metropolitan Board of 
Works by Mr. Bazalgette and Mr. Keates, the engineer and 
chemist appointed to examine the working of the celebrated 
A. B. C. process at Crossness are very damaging to the 
prospects of the company. Mr. Bazalgette states that during 
a period of three months, during which the inspection lasted, 
142 tons of the so-called native guano were manufactured at 
a cost of <£895. At this rate the manure costs £6 6s. 4 cl. 
per ton, “ exclusive of rent, interest on capital, depreciation 
of plant, and other incidental items.” The manager of the 
company objects to this calculation that a portion of the ex¬ 
pense—that for pumping,, for instance—was accidental, and 
should not be counted in the cost of the manure. But even 
if an absurdly liberal deduction be made on this score, the 
manure, it is evident, could not cost less than £4 per ton. . 
Mr. Keates reports that the finished manure contained 
nothing of any value but 0 929 per cent, of ammonia and 
0*48 per cent, of phosphoric acid, and that at the present 
market price of these substances, the manure is therefore 
worth something less than £l per ton. 
