UTILIZATIOX OF THE FISH WASTE OF THE PACIFIC OCEAX. 25 



The averages of all experiments show the following facts : Each ton of salmon 

 offal treated produced 800 pounds of mixed oil and fertilizer. Of this amount 

 200 pounds was salmon oil and 600 pounds oil-free fertilizer. The average 

 analysis of the fertilizer thus produced was — ammonia, 14.3 per cent ; bone 

 phosphate, 13 per cent. 



Estimating the 200 pounds of oil as being 25 gallons, at a price of 32 cents, 

 which seems a fair average, we have, then, for each ton of offal treated an oil 

 value of $S, and, estimating the value of a unit of ammonia at 83.20 and bone 

 phosphate at 10 cents per unit, we have a fertilizer value at — 14.3 per cent am- 

 monia, at $3.20, $45.76 ; 13 per cent bone phosphate, at 10 cents, $1.30 ; or a total 

 value of $47.06 per ton. 



Then, at 600 pounds of fertilizer of this quality to the short ton of offal 

 treated, we have $47.06 X0.3=$14.12, the fertilizer value of 1 ton of offal, which 

 gives a total available value of 1 ton of offal as — fertilizer, $14.12 ; oil, $8 ; 

 total value, $22.12. 



METHODS OF DISPOSAL OF WASTE. 



It already has been stated that the first waste incident to the sal- 

 mon-canning industry consists of throwing overboard the fish unfit 

 for food and food fish for which there is no demand taken inciden- 

 tally with the salmon. It has also been pointed out that the second 

 waste, considered in the order of the manipulation of the fish prior 

 to canning, consists in the occasional discarding of scowloads of 

 salmon for which there is no demand. 



In the succeeding operation of dressing the fish the head is severed 

 first. If severed mechanically it falls directly into a chute leading 

 beneath the cannery floor; if by hand, it, together with the viscera, 

 is washed into a chute by water flowing through a trough at the back 

 of the " butchers' " table. "Where the dressing is mechanical, the sev- 

 ering of the head and the removal of the viscera are performed as 

 separate operations by the same machine. The head falls into a 

 chute which directs it beneath the cannery floor. The viscera fall 

 through an opening in the floor situated directly beneath the ma- 

 chine. As there is considerable spattering, the floor around the 

 machine is liberally covered with the waste. After a consignment 

 of fish has been cleaned, or at the end of the day's work, the mate- 

 rial on the floor is washed into the opening beneath the machine, or 

 through the cracks, purposely large, in the floor. That produced 

 by the operations of the " slimers " likewise is conducted beneath 

 the cannery floor. From this point, all of the waste, whatever its 

 source, is treated together or similarly. 



In southeastern Alaska the common practice is to permit all the 

 waste to fall into the water beneath the cannery. As it is heavier 

 than water it sinks to the bottom. In certain instances it is 

 exposed at low tide (see PL V), though generally the water is of 

 sufficient depth to cover it. In certain localities it is devoured 

 by dogfish as fast as produced, while at other canneries a few 

 59351°— Bull. 150—15 4 



