Composition of Bones taken from the Guano. 197 



the existence of uric acid, was evident; on re-solution in water 

 a pale brown flocculent matter separated (c), similar to what 

 had been just noticed; this was separated by a filter and 

 weighed 0*11 gr. ; the solution was then evaporated to dryness 

 and heated to expel the excess of sulphuric acid which had 

 been added; the residue (<i) of bi-sulphate of potash weighed 

 7'85 grs., equivalent to 2'94' grs. of potash. The second half 

 of the solution was treated with caustic potash and submitted 

 to distillation until I'educed to a very small volume, the vola- 

 tile products being passed into dilute hydrochloric acid ; to 

 this a solution of chloride of platinum was added, and the 

 whole evaporated to dryness and then re-dissolved in a mix- 

 ture of alcohol and aether, which left 3'44' grs. of ammonio- 

 chloride of platinum, equivalent to '26 gr. of ammonia (e). 



We have, therefore, from this analysis, the following re- 

 sults : — 



Sulphuric acid {b) 3*00 grs. x 2 = 6*00 grs. 



Potash {(l) . . . 2-94 ... x 2 = 5-88 ... 



Ammonia (<?) . . 0-26 ... x 2 = 0*52 ... 



Flocculentmatter (c) 0-11 ... x 2 = 022 ... 



Insoluble {a) . , \ Ti^ ... 



If we now arrange the bases with the acid to form salts, we 



shall have — 



Potash . . . 5*88 grs.l , r» -o i i c ^ \ 



oil • -1 ^ r>/A >- =10'/8grs. sulph. or potash. 



Sulphuric acid . 4*90 ... J ^ ^ * 



Ammonia . . . 0*52 ... 1 



Sulphuric acid 1-22 ... 1 2-29 ... sulph. of ammonia. 

 Water ot crystal- \ ^ ( * 



lization . . ./"'^^ - J 

 There is, however, a deficiency in the experimental quantity 

 of sulphuric acid amounting to 0*12 gr., as will be seen on 

 comparing this arrangement with the analytical results. These 

 two salts appear to be associated in this substance in atomic 

 proportions, thus: — 



Theory. Experiment. 

 Sulphate of potash 4 eqs. = 10-8 lO'TS 



Sulphate of ammonia 1 eq. = 2-3 2*29 



It will be evident from the above examination, that this 

 substance is not perfectly constant in its composition ; for in 

 the first quantitative analysis a small quantity of phosphate of 

 lime was present, which did not exist in the portion which 

 formed the subject of the second analysis, nor in that of the 

 qualitative examination. 



The curious question which arises from these investigations, 

 is as to the probable source of the sulphate of potash in a sub- 

 stance taken from the midst of a material, the guano, abound- 

 ing in soda and ammoniacal salts, and for the moment this 



