I 



4G3 



therefore, that any goods containing more than 1 percent of iron shoukl be regarded 

 as of mineral rather than of bone origin. In the case of the silica it was fonud that 

 the quantities in the bone goods varied much more widely. p]xcluding a sample 

 [thought to be adulterated], it is observed that the bone in no case contained much 

 more than half as much as the minimum found in the dissolved rock. The differ- 

 ence should be still greater in the case of dissolved bone. 



It would seem, in conclusion, that either of these methods might aid very greatly in 

 the discrimination between different phosphates, although probably that in which 

 iron is used as a characteristic might often be used more satisfactorily than the 

 sec(md method. Neither method entails work requiring any considerable apparatus 

 or time. 



The composition of bone of various degrees of fineness 

 AS found in cojimkrcial ground bone, W, Frear, Ph. I), (pp. 

 190-103). — To observ^e tlie dirterence in composition of particles of bone 

 of difteient lineness, analyses were made of five samples of bone 

 "picked at hazard from a large number." Each of these was separated 

 by screening into tine, fine medinm, medium, and coarse particles, the 

 fine including particles less than one fiftieth, the fine medinm less than 

 one twenty-fifth, the medinm less than one twelfth, and the coarse over 

 one twelfth of an inch in diameter. The results of the analyses of each 

 grade of bone from the several samples follow : 



Composition of hone of differtnt fprides of fineness. 



In general the percentage of both phosphoric acid and nitrogen 

 increased with the coarseness of the particles, being perceptibly 

 higher in the coarse than in the fine particles. The effect Avhich these 

 differences in composition of the particles might have on the calculated 

 commercial valuation of the bone is considered, and the conclusion 

 is reached that "for the purpose of valuation any bone may be assumed 

 to be identical in composition in all its grades of fineness, without 

 unfairness to either manufacturer or consumer." 



Composition and fertilizing value op tannery ashes, W. 

 Frear, Ph. D. (pp. 194, 19.")). — A summary of the results of analyses 

 by Storer* of fresh and spent tan, and of leached and unleached wood 

 ashes, and an analysis of one sample of ashes from spent tan. 



Xitrogen supply of corn, W. Frear, Ph. J)., and H. P. 

 Armsby, Ph. D. (pp. 195-206, plates 4). — The questions investigated 

 were: "(1) Can corn take up any of its nitrogen indirectly from the 

 a-tmosphere through the agency of the microorganisms present in the 



* Bulletin of the Bussey Institution, vol. ii, pp. 26-50. 



