FISH-SCRAP FERTILIZES IXDUSTRY OF ATLANTIC COAST. 25 
automatic conveyor which supplies the fish to be cooked, while along 
either side of the double row are placed other tracks running to the 
presses. 
Fish are dumped into the vats in quantities depending on the 
capacity of the vats, usually 50 to 100 barrels, some water is added, 
and the steam is turned on. They are cooked about 20 minutes, or a 
sufficient length of time to cause them to break up easily, but not long 
enough to disintegrate them entirely. The object of the cooking is 
to break the oil cells or to bring about that condition which admits of 
a more ready expressing of the oil. If the cooking is too prolonged 
this is accomplished also, but the flesh is so thoroughly disintegrated 
that it becomes a mush from which it is difficult to separate the oil. 
The oil, water, and fine particles of flesh would squeeze out of the 
presses together. 
PRESSING (OLD METHOD). 
The cooked fish are thrown from the vats into the curbs of the 
presses by means of a modified shovel which retains the solid matter 
and permits the water to run back into the vats. The curbs are 
mounted on trucks and are brought alongside the vats by means of 
the track, spoken of above, which parallels the rows of vats. The 
curbs are generally tubs, whose cross section is a circle, constructed 
of metal slats with an outward slant. The spaces between the slats 
are of a suitable width to permit the water and oil to escape when the 
pressure is applied, but to retain the solid matter. The spaces are of 
the same width from top to bottom, since the outward slant of the 
slats is compensated for by the increased width of the slats. The 
bottom is hinged, and, while securely fastened, its lock is readily 
manipulated and the bottom easily released. An iron shield is gen- 
erally placed around the curb to protect the workmen from the jets 
of water and oil which escape from the curb when pressure is applied. 
The curb, when it has received its charge of fish, is rolled back 
beneath the press and the power is applied. In certain of the smaller 
factories in the Beaufort region screw presses, manipulated by hand, 
are still in use. Most of the other plants using the older, discon- 
tinuous method of expressing the fish, however, are equipped with 
hydraulic presses. 
The escaping water and oil is caught by the properly slanting 
floor as is also that escaping from the curb during charging and 
conveyed to the oil room for settling and further treatment. When 
the maximum pressure has been applied and no more liquid is being 
forced out the pressure is released, and the curb is rolled over an 
opening in the floor for emptying. The bottom is then released and 
swings downward, and the mass of fish scrap falls in a solid cake to 
the floor below. The slanting sides of the curb are designed to 
5781°— 13 4 
