1894.] 





Fig. 



8. 



)> 



9. 



!> 



10. 



)) 



11. 



;) 



12. 



)) 



13. 



)) 



1*. 



)) 



15, 



!) 



16. 



» 



17. 



)) 



18. 



P. C. Kay — Chemical Examination of Food Stuffs. 59 



Cyrestis theresce, n. sp., d', p. 18. 

 Neocheritra namoa, n. sp., cf , p. 41. 

 Charana cepheis, n. sp., cT, p. 40. 

 Gerydus gallus, u. sp., ? , p. 25. 



,, gcetulus, n. sp., ? , p. 24. 



„ gigantes, n. sp., ? , p. 23. 

 Paragerydus pori -Li7ius, n. sp., c/", p. 27. 

 Plastingia vermiculata, Hewitson, <f, p. 56. 

 Camena cremera, n. sp., cf, p. 37. 

 Sinthusa aspra, Doherty, <f, p. 44. 



„ nialiha, Horsfield, <f, p. 43. 



On the Chemical Exa7nination of certain Indian Food Stuffs. Part I, 

 Fats and Oils. — By P. C. Ray, D. Sc. Communicated hy Alex. 

 Pedler, F.R.S. 



[Read February 7tli.] 



Of late years a belief has been gaining ground in Calcutta, Bombay 

 and in many other important towns in India, not apparently without 

 reason, that wholesale adulteration is practised in many of the common 

 articles of diet, notably in ghee, butter, milk, mustard oil, &c. The 

 present investigation was undertaken with a view to throw some light 

 on these points, and it embodies the results of work carried on at 

 intervals during the last four years. 



PRELIMINARY. 



As butter enters largely into the dietary of the people of Europe 

 and America, abundant work has been done by Chemists on its analysis. 

 It is, however, well-known that the composition of milk and of the butter 

 made from it is, within certain limits, dependent on the breed, climate, 

 method of feeding the cows, period of lactation, and so on. The standard 

 for genuine butter as generally accepted in England, especially at 

 Somerset House, cannot therefore be always accepted as a safe guide in 

 this country. 



The analysis of the fixed oil of mustard and the various other oils 

 with which it is generally sophisticated also presents considerable diffi- 

 culties. Not much work has been done in this field. The history of the 

 substances which have been subjected to analysis is seldom given, and 

 the experimental methods are not generally described in sufficient detail 

 to enable the results to be compared. While the information available is 

 meagre on the one hand, the results published from time to time are in 

 themselves in some cases contradictory. It was thus found to be 



