178 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



the i)roportion of moisture to be reduced to 11.45 per cent., or about one- 

 fiftb that contained in the scrap fresh from the press, and the proportion 

 of oil to 4.65 per cent., thus proving that the content of oil in the washed 

 scrap as it came from the press (before drying it) had been reduced to 

 less than 2i per cent. According to these figures, the proportion of oil 

 hitherto lost is, by the new process, reduced from an average of, say, 15 

 per cent, of the weight of the scrap as it commonly issues from the press, 

 to about 2 per cent. ; the balance, say, 12 or 13 per cent., is saved. Let 

 it be assumed, however, that only 10 per cent, can be realized in prac- 

 tice, and that the annual outturn of scrap from the factories of the 

 Maine Association is only 40,000,000 pounds. This would give an an- 

 nual saving of 4,000,000 pounds of oil, or 533,000 gallons, worth at cur- 

 rent prices at market for 1877, 40 cents per gallon, $213,200." 



Proposed chemical methods. 



250. Other methods of extracting the oil from fish scrap have been 

 proposed, but their adaptability is not yet so certainly proved as to war- 

 rant their adoption by manufacturers. 



The proposed plans involve the use of the fumes of benzine, or bisul- 

 phide of carbon, which are brought into contact with the fish in air-tight 

 chambers. The oil is absorbed by these substances, and collects in tanks 

 in the floors of the chambers. Any surplus of benzine or bisulphide of 

 carbon which may remain in the oil is expelled by distillation. 



The naphtha process for extracting the oil, remarks Mr. Maddocks, 

 consists in subjecting the scrap, in an inclined iron cylinder, to the 

 action of vapors of naphtha, which combine with the oil, and the latter 

 in a state of solution filters away at the lower end of the cylinder. 

 The naphtha is then recovered by evaporation. The process is slow, 

 costly, and dangerous. 



Proposed mechanical methods. 



251. It has been suggested that a recently invented filter-press, the 

 invention of Mr. John Bowing, is well adapted for the extraction of oil 

 from the menhaden and the formation of the residue into cakes. It is 

 probably too small for the extended operations of manufocturers, but 

 may be very serviceable for the use of refiners. Mr. C. B. Norton, 25 

 Astor House, K. Y., is the American agent. 



44. — Value of fish for manufacturing purposes. 



Prices of fish at different seasons. 



252. The price of fresh menhaden cannot be definitely stated, since it 

 varies from week to week with the abundance and fatness of the fish 

 and the needs of individual manufacturers. 



Many factories rely entirely upon their own "gangs" for their sup- 

 plies ; some others buy the fish of the vessels engaged in the trade. 



