300 
On the Analysis of Guano. 
3. The solution being acidulated with nitric acid, was treated with 
acetate of barytes, in a quantity equivalent to the sulphuric acid present, 
and it afforded 12 parts of sulphate of barytes. With the filtered liquor, 
700 water grain measures of ferric acetate were mixed, and then am- 
monia in excess; 18 '5 parts of washed and ignited subphosphate of 
iron were obtained, from which 8 '8 parts present in the acetate being 
deducted, 9' 7 remain as the quantity of phosphoric acid; but 9" 7 of 
acid produce 13 "25 of biphosphate of ammonia, which contain only 
2'3 of ammonia, combined with 0'95 of water, or its elements. From 
the alkaline excess in the guano, there can be no doubt, however, that 
it contained the subphosphate (found in the urine of Carnivora), and 
not the bipliospliate of that base. In this case, 9" 7 of acid produce 
14*32 of dry saline compound, containing 4 '62 of ammonia, which, 
with the 0"34 of ammonia in the carbonate, constitute a sum of 4 '96. 
To the liquor freed from the phosphate of iron, and acidulated with 
nitric acid, acetate of lime being added, 3 '33 parts of oxalate of this 
base were obtained, which are equivalent to 3 "23 oxalate ammonia, 
containing 0'89 of ammonia. 
4. Nitrate of silver now produced from the filtered residual solution 
8 parts of chloride, corresponding to nearly 3 of sal ammoniac, which 
contain nearly 0*9.t of ammonia. 
5. The 53 parts insoluble in water were digested with the solution of 
borax at a boiling heat, thrown on a filter, and the uric acid being 
precipitated from the filtrate by means of a little hydrochloric acid, 
washed and dried, was found to weigh 13 5 parts. There were left on 
the filter 36 '5 parts, dried at 212° F., so that 3 parts of soluble organic 
matter had passed through the filter. These 36 ' 5 parts lost by ignition 
only 9 7 parts in organic matter, became white, and afforded a very 
faint effervescence with hydrochloric acid, showing that a very little 
oxalate of lime had been present. 1*25 parts of silica were left after 
the action of the acid. To the solution of the 26 •.'j5 parts, sulphuric 
acid was added, and the mixture being heated to expel the hydrochloric 
and excess of sulphuric acids, the residuary matter was digested and 
washed with dilute alcohol, and thrown on a filter ; the solution of 
magnesia passed through, while the sulphate of lime remained. After 
ignition, this weighed 27 '5 parts, equivalent to 22 of subphosphate of 
lime. On supersaturating the filtrate with ammonia, 4'5 parts of the 
magnesian ammonia phosphate were precipitated, containing 0*32 of 
ammonia. With the 13"5 parts of uric acid, 1*23 of ammonia had 
been originally combined, forming 14*73 of urate. 
6. 25 grains of the dry guano aflbrded, by ignition in the combustion- 
tube along with 200 grains of the mixed lime and hydrate of soda, 
4* 165 of ammonia, which correspond to 16 "66 in 100 parts of the dry, 
or to 15 "244 in the natural state; leaving therefore 5 parts for the 
quantity of potential ammonia, or of ammonia producible from the 
decomposition of its azotized organic matter. This guano is therefore 
well adapted to promote permanently the fertility of a soil. It yields 
besides to alcohol a notable quantity of urea, which I did not think it 
worth while to determine quantitively, and from which undoubtedly 
n portion of the ammonia proceeded, in the distillation with milk of 
lime. 
