226 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



ing aud grindinjif. The process is said to be easy, simple, and efl'ectual. 

 The maiu drawback is the necessity for new apparatus and the rejection 

 of a good share of the appliances now used. 



Two samples offish guano prepared in this way and analyzed at the 

 Connecticut experiment station gave, respectively : 



Per cent. Per cent. 



Moisture 4.91 3.67 



Oil 2.07 



Nitrogen 10.78 10.74 



' Immense waste offish at present. — Possibilities of future manvfacture. 



295. The accounts of these new processes at my disposal are meager. 

 They seem, however, to promise well, and, if successful, must revolu- 

 tionize the manufacture of fish guano. The great desideratum has been 

 a means of removing the oil as entirely as possible, saving the nitro- 

 genous matters aud yielding a fine, dry product. This seems to have 

 been found. I understand that the Adamsou process is to be used in 

 the manufacture of a fertilizer from the fish that are taken along the 

 coast, but thrown into the sea again on account of their low value for 

 oil or food. The benefit to our agriculture from such an economizing of 

 fish hitherto wasted would be immense. Concerning the number offish 

 thus lost Mr. Goode writes : " I estimate that the amount of fish 

 annually thrown away from the hundred and tifty-odd weirs on our 

 coast cannot fall much short of ten millions of pounds annually, and 

 probably far exceeds that." 



^^ Acidulated fish " and "j^s/t and potash salts." 



29G. The " acidulated fish " (class No. 6 on page 219) is prepared by 

 treating the fish scrap with sulphuric acid to render the phosphoric 

 acid more soluble. Unfortunately the constitution of the tissues of the 

 fish is such as to resist the action of the acid, and the desired result is 

 only partly attained, A sample examined under the writer's direction 

 gave 7.09 per cent, of phosphoric acid, of which only 1.70 per cent, was 

 soluble in water. 



It will be remembered that Pettitt's process for the manufacture of 

 fish waste into a fertilizer was based upon treatment of the fish with 

 acid, and did not prove a success. 



Various efforts in this same direction are reported in this country and 

 in Europe, but none, as I can learn, have been found ijrofitable. The 

 imperviousness of the tissues to the action of the acid has thus fiir been 

 an insurmountable obstacle to success, and will probably remain so. 



The " fish and potash salts " (class No. 7, above) is a mixture, as its 

 name represents, of fish, half-dry scrap apparently, in the specimens I 

 have seen, with German potash salts. The idea is a sound one, in that 

 the salts used, doubtless of the lower grades, like Leopoldshall Kaiuit, 

 aud containing large percentages of chloride of sodium (common salt). 



