5"68 Observations on the Otis dmmonoides of Hodgson. £Jtjn«; 



should give 22.20 ; an old Sicca rupee 22.15, — each tenth of a grain 

 being the equivalent of one dwt. If more than 22.00, the silver is 

 better, if less than 22.00, it is worse than our standard. But the 

 silver obtained in this experiment is usually somewhat heavier than it 

 should be, being associated with a little copper. The error is nearly 

 compensated by the slight loss in the manipulation, and moreover it 

 does not amount to more than one dwt. of excess. This may be safely 

 allowed for, and the extempore assayer may rest satisfied that he knows 

 the true value of his silver within 1 per 100. Thus for example, he 

 dissolves 24 grains of a Debmohree rupee, and he finds his dry silver 

 weighs 13 grs. It is therefore 9.0 grs. (or 90 dwt.) worse than 22 grs. 

 which should be the standard. Now as 24.0 :: 13.0 :: 100 :: 54.16, 

 or 100 tolas of this silver contain fine silver 54.16 = 59.08 Co.'s Rs, 

 But if an error had occurred increasing the weight of the silver preci- 

 pitate to 13.20 the per centage of fine silver would be 55.004--^ alloy 

 -=to Co.'s Rs. 6.0, the difference being 0.84 per 100 on the fine silver,, 

 or 9-10thsof a rupee. But in the transactions to which these remarks 

 bear reference an error of even one per 100 at either side is of but 

 insignificant importance, the object being merely to obtain a good ap- 

 proximation, not an absolutely correct result. 



The use of pure copper is essential for this simple process, inasmuch 

 as the impurities of the metal usually met with may lead to very 

 deceptive results. I shall be happy to supply any reader of this paper 

 with electrotype copper in sufficient quantity to enable him to try his 

 skill as an amateur assayer— -for pure nitric acid I must refer him to 

 the Hon. Company's Dispensary, or to any of the eminent Calcutta 

 druggists. 



Observations on the Ovis Ammonoides of Hodgson, by Cagt. T. 

 Hutton, F. G. S. 



Having lately procured a pair of skins of the (so called) " Ovis 

 Ammonoides" of Hodgson, and as the specimens are both in winter 

 pelage, as indicated by the beautifully soft wool under the hair, it may 

 be interesting to compare the description of them with that lately 

 published by Mr. Hodgson, in the Journal Asiatic Society, No. 1*73, 

 of 1846 



