228 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



conveniently inserted here, and of too much interest to be condensed, 

 and are therefore given in the Appendix O. 



50. Chemical composition of menhaden and of fish manures. 



A)iali/sis of loliole menhaden ayid of flesh and hones ofichale. 



298. The only analysis of whole menhaden 1 have noticed is given by 

 Prof. G. H. Cook.* The specimens were taken in the Earitan Kiver 

 the latter part of October. 



" Five of the fish weighed four and one-fourth pounds — their average 

 weigiit being three quarters of a pound. The oil was first separated by 

 adding water to the fish and boiling until the flesh was reduced to a 

 pulp. The oil was then skimmed off and purified from water and other 

 substances by ether. It then weighed 2.G6 ounces, which is equivalent 

 to 3.914 per cent, of the original weight of the fish. The substance of 

 the fish remaining was then strained out and carefully dried in an air 

 bath, at a temperature of 290° F., when the dry mass was found to weigh 

 11.8 ounces. On account of the solvent power of the sulphuric acid, 

 which was added to the fish, it was thought proper to separate all the 

 mineral matters from the fluid in which the fish had been boiled, add 

 them to the dried fish, excluding of course the sulphuric acid. These 

 weighed 1.1 ounces, and added to the weight of dried fish given above, 

 11.8 ounces, made for the whole weight of the dried matter 12.9 ounces, 

 which is equivalent to 18.93 per cent, of the original weight of the fish. 

 There was still left in the fluid some animal matter, which could not be 

 satisfactorily separated, and was left out. The water in the fish was 

 77.15 per cent, as ascertained by deducting the percentage of oil and 

 dried matter from 100. The nitrogen in the dried fish was ascertained 

 by ultimate analysis to be 7.70 per cent., which is equivalent to 9.28 per 

 cent, of ammonia. The mineral substances contained in the fish were 

 freed from the organic matter by pressing, and then separated from 

 each other by the ordinary process of analysis." 

 Analysis of the fresh fish. 



Water 77. 150 



Oil 3.914 



Dried fish 18. 936 



Analysis of the dried fish. 



Lime 8. 67 



Phosphoric acid 7. 78 



Silicic acid 1. 33 



Potash 1. 54 



Soda 1.02 



Magnesia 0. 67 



Chlorine 0. 69 



Organic matter and loss ... 78. 30 



100. 00 



* Geology of New Jersey, 1868, p. 497. 



