THE MENHADEN FISHEEY. 343 



the New Jersey coast, aud formerly they were salted down in New England for export to the West 

 Indies. They are also used as bait in various fisheries. 



The factories are located at various points along the coast, convenient to the fishing grounds. 

 At the eastern end of Long Island there are a large number of factories, fitted to handle great 

 quantities of fish. Oue of the largest and best-equipped factories is that of Joseph Church & Co., 

 at Tiverton, E. I. Aloug the Connecticut and New Jersey shores there are several factories, aud 

 in Chesapeake Bay upwards of sixty, many of them, however, very small. The processes of man- 

 ufacture arc fully described in another part of this report. 



METHODS OF OIL MANUFACTURE. 



THE PRINCIPLES INVOLVED. The manufacture of menhaden oil is simple in the extreme, con- 

 sisting of three processes boiling the fish, pressing, and clarifying the expressed oil. The appa- 

 ratus absolutely needful is correspondingly free from complication, consisting, for the first process, 

 of a cooking vessel; for the second, a press; and for the third, a shallow vat or tank. These were 

 used twenty-five years ago by Mrs. Bartlett, the manufacturer of the first menhaden oil, who pro- 

 duced an article little inferior to the best now in the market. Very few patents for improved 

 methods of manufacture have been granted. Mr. W. D. Hall's patent for steam-rendering is the 

 most important. The principal changes have been in the introduction of labor-saving appliances, 

 which enable manufacturers to carry on their business with the smallest possible force of workmen. 

 Steam, is of course an important auxiliary in handling the fish and in working the presses, and is 

 also used to great advantage in heating the cooking-tanks, as well as for pumping the water and 

 oil. The hydraulic press has replaced the old-fashioned screw-press in most of the larger estab- 

 lishments, and the size, shape, and arrangement of the bleaching vats, as well as the methods of 

 drawing and pumping the oil from one to the other, have been perfected. 



PROCESSES EMPLOYED IN MANUFACTURE. The process of oil-making at the larger works is 

 essentially as follows: The fish are conveyed to the upper story of the factory on wooden tram- 

 ways in cars containing about 20 barrels each, and are dumped into large reservoirs, from which 

 the cooking-tanks are replenished from time to time, or are emptied directly into the cooking-tanks, 

 whi ;h are filled to the depth of 6 inches with sea- water. From 50 to 75 barrels are placed in each 

 cooking-tank, and then steam is turned on and they are boiled for half an hour or more. In this 

 way about two-thirds of the oil is separated; the remainder is expressed by means of the hydraulic 

 presses, under a pressure of 50 to 150 tons or less, the fish having been placed in circular curbs of 

 half inch iron, perforated with holes an eighth of an inch in diameter, each curb having a capacity 

 of 3 to 10 barrels. The oil, mixed with water, is now run into the "drawing-off tanks" while it is 

 still hot, and is passed through several of them, the water separating and sinking to the bottom. 

 The oil is now drawn off into a "settling- tank" of 4,000 or 5,000 gallons capacity, where it remains 

 a few hours to allow impurities to sink to the bottom. Finally, it is pumped into " bleaching- tanks," 

 containing several thousand gallons, where it becomes clearer and whiter in the rays of the sun, 

 and after one or two weeks of exposure is ready for shipment. 



PROCESSES EMPLOYED IN REFINING. Boardmau & Atkins make the following statements 

 about processes of refining: 



"The oil and water running together into the receivers separate by the oil rising to the top, 

 whence it can be drawn or skimmed off. Great pains must be taken to separate the oil from the 

 water before the impurities contained in the latter begin to ferment, for if this happens the quality 

 of the oil suffers much. Moreover, in what appears at first to be pure oil there is a variable amount 

 of finely divided fleshy substance that must be allowed to settle, as it will after a while, and the 



