UTILIZATION OF THE FISH WASTE OF THE PACIFIC OCEAN. 39 
RENDERING APPARATUS. 
The equipment and operation of the large-scale rendering stations 
now in successful operation have been described compositely in 
foregoing paragraphs. A strictly conservative procedure would be 
to adhere to demonstrated methods. However, since these methods 
once were in universal use on the Atlantic coast and now have been 
discarded almost universally to make way for new methods, a dis- 
cussion of new methods, and even a recommendation of their cautious 
adoption may be justified. 
The only process which has been applied with any success to the 
rendering of this class of material on the Pacific coast, it has been 
shown, is discontinuous. The apparatus required by this process 
may be installed and operated in small units, necessitating a multi- 
plication of the labor involved, or in large units, involving more 
labor than the small units, of course, but not proportionately. Since 
the material to be treated is secured in irregular and uncertain 
amounts, a number of small units would afford more of the required 
elasticity than an equivalent number of large units, but the cost of 
labor required to operate such a number of small units soon would 
become prohibitive. So, by nature, this apparatus offers serious 
objections to its adoption in the large-capacity plants. 
The continuous and automatic machines for cooking, pressing, and 
diying in use in the fish-rendering industry of the Atlantic coast 
should lend themselves readily to adaptation to that industry on the 
Pacific coast. These make possible the cooking, pressing, drying, 
and intermediate handling of the fish entirely by machinery, with a 
high efficiency and minimum expenditure of labor. The unloading 
is done by elevators, which deposit the fish in storage bins, from 
which they are fed into continuous steam cookers, long tubular cham- 
bers through which the fish are moved by a rotating screw, being 
played upon by jets of steam. Thence they are transported by con- 
veyors, into which they are fed, to the power presses. These are steel- 
slatted cones, through which the cooked fish are forced by a rotating 
screw. As they move toward, and before they can pass out of, the 
small end of the cone, they are squeezed into a very small compass. 
This pressure rids them of the greater portion of their water and 
oil. From the press they are conveyed, again entirely automatically, 
into a direct-heat, rotary, hot-air drier. 
A plant designed for the treatment of 100 tons of cannery waste 
per day and equipped with the automatic machinery complete would 
cost about $35,000. This estimate 1 is based on the following items. 
1 The itemized statement of the cost of equipment and plant is made possible through 
the courtesy of Mr. Philip Renneburg and Mr. P. Burgess, of Baltimore, Md. 
