FISHERY INDUSTRIES OF THE UNITED STATES. 19 
of canning the usual species which will yield standard packs and to 
the solution of the practical problems of the canners. For example, it 
is making a caratul investigation of the possibilities of recovering the 
fry bath oil and of keeping it free from the objectionable substances 
acquired by continued use. This problem is much more complex 
than was anticipated when the work was undertaken and, if it can be 
solved, it will be of marked value to the industry. 
PRESERVATION OF FISH NETS. 
Most of the investigations in the preservation of nets have been 
made in Norway, very little investigation or experimentation being 
noted in the fishery or scientific journals in other countries. This 
important means of economizing in the expense of nets appears to 
have been largely neglected in the United States, the principal 
reservative used being tar, which can be used only for the coarser 
Sits of nets. As the fishing gear employed by our fishermen repre- 
sents an investment in excess of 15 million dollars, a large part of 
which is in twine, and in view of the increased cost of such netting, 
the importance of lengthening the life of such gear will be appreciated. 
To contribute to this end, a paper on the subject has been prepared,‘ 
reviewing the literature of the subject, presenting the fundamental 
principles so far as they are known, and giving for use those recipes 
which, from a chemical standpoint, seem best calculated to serve 
their purpose. In addition provision is being made for the conduct 
of additional tests for the purpose of affording still further aid to ovr 
fishermen. 
INCREASING THE USE OF BY-PRODUCTS OF FISHERIES. 
Although the Bureau’s activities in this field during the year were 
practically confined to suggestions through correspondence or by 
personal visits, the results achieved have been exceedingly gratifying 
and important progress is to be noted in the saving of fish waste, 
the manufacture of fish meal, the production of fish enenae and the 
utilization of fish scales. The decline in value of fish oil and scrap to 
prewar levels wiil undoubtedly affect operations in 1921. 
FISH OILS. 
By converting the figures published by the Bureau of the Census 
in Animal and Tegetable Fats and Oils for calendar years 1919 and 
1920, on the basis of 74 pounds to the gallon, the production of fish 
ous in gallons in 1920 was as follows: Menhaden oil, 3,676,453; 
whale oil, 3,073,574; sperm oil, 416,737; herring oil, 380,379; cod 
and cod-liver oil, 196,108; and all other, including marine animals, 
1,060,322; a total of 8,803,574. On the basis of reports from the 
Pacific Coast States and Alaska, the production of fich oils in 1920 
approximated 3,066,000 gallons. 
mports of fish oils entered for consumption for the calendar year 
1919 amounted to 2,599,072 gallons, valued at $2,928,993. This 
4 Taylor, Harden F.: Preservation of Fish Nets. pendix IV, Report, U. S. Commissioner of Fisheries 
for 1920, 35 p., 1 fig., B. F. Doc. 898. Washington, 1921. 
