80 17. S. BUREAU OF FISHERIES. 



building the pot clear to the bottom, which would be expensive, as 

 the pots of the traps are usually in quite deep water. If the trap is 

 intended to catch the fish coming from only one direction, the lead 

 generally runs to and is attached to one side of the entrance to the 

 outer heart on the side opposite to that from which the fish are 

 expected. 



Some traps have "jiggers" (a hook-shaped extension of the outer 

 heart) on each side, and sometimes on only one side, which help 

 to turn the fish in the required direction. 



The "pot" is built out beyond the inner heart and immediately 

 adjoining same. It is a square compartment, with web walls and 

 bottom connected in the shape of a large square sack, fastened to 

 piling on all sides. Tliis pot is hauled up and down by means of 

 ropes and tackles, either by hand or, as is most popular, by steam. 



The "spiller" is another square compartment adjoining either end 

 of the pot (sometimes there are two spillers, one at each end), and is 

 simply a container for fish. A small tunnel leads the fish from the 

 pot into the spiller, whence the fishermen lift them out. This is 

 accomplished by closing the tunnel from the pot, after which the 

 ropes holding the front of the spiller are loosened and the net waU 

 allowed to drop almost to the level of the water. A steam or gasoline 

 tug then pushes a scow alongside the spiller and takes position on the 

 outside 01 this scow. From the deck of the tug a derrick is rigged 

 with a running line from the steam capstan through the block at the 

 top of the derrick. This line is attached to the far end of a net apron, 

 called a "brailer," which is heavily weighted by having chains along 

 each side and leaded crossways at several places. A small boat is 

 run inside the spiller, and the men in this draw the brailer across the 

 barge and let it sink in the spiller. The fish soon gather over it, 

 wh<>n the steam capstan quicldy reels it in, the net folding over as 

 drawn in from its far side and spilling the fish out on the scow. Men 

 on the scow pick out and tlu^ow overboard the undesirable fish. The 

 apron is then drawn back across the pot and the operation repeated 

 so long as any fish remain. In this manner a trap with many tons 

 of salmon in it is quickly emptied. 



Traps, like nearly all other fixed fishing appliances, are built on 

 the theory that salmon, like most other fishes, have a tendency to 

 foUow a given course in the water, whether a natural shore line or 

 an artificial obstruction resembling one; also that the fish very seldom 

 turns in its own wake. The trap has taken advantage of these natural 

 tendencies of the lish, and is arranged so that, although the salmon 

 may turn, he will continually be led by the wall of net toward and 

 into the trap. 



If a trap is located in a place where fish play and where an eddy 

 exists, and the fish run one way ^vith the incoming tide and the 

 opposite with the outgoing, it vnW fish from both directions; if located 

 where the fish simply pass by, as for instance, on a point or reef, it 

 will fish from one siae only. 



A variation of the trap, to be used in places where piles can not be 

 driven, is the floating trap. An experimental trap of this variety 

 was used at Uganuk, on Kodiak Island, Alaska, as early as 1896. 

 Its use was abandoned in 1897, not to be resumed until some years 

 later. A number of floating traps (of the type invented by J. R. 

 Heckman, of Ketchikan, Alaska) have been and are being used in 



