22 FISHERY INDUSTRIES OF THE UNITED STATES. 
glass spheres is coated with this essence and the cavity filled with a 
hard ae wax. 
In the past the best seales for the purpose were obtained from one 
of the cyprinid fishes of Europe. The supply of pearl essence was 
curtailed by the outbreak of the Great War, and in 1915 and 1916 
numerous inquiries were received by the Bureau concerning the 
fishes from whose scales the essence could be prepared and details of 
manufacture of the essence and of artificial pearls. Such informa- 
tion as could be found was supplied, and some experiments were 
made with the scales of native fishes. Promising samples, although 
never free from color, were made from the scales of the alewife, or 
river herring. After treating the scales with ammonia the lustrous 
particles were separated out by centrifugation. Samples submitted 
to American representatives of Parisian pearl manufacturers were 
pronounced off color and lacking in luster. Later one of the Bureau’s 
technologists made some additional experiments, including the diges- 
tion of the proteinaceous material, leaving the lustrous particles and 
a pearly suspension produced, but the results were not wholly satis- 
factory. At about this time others had succeeded in making pearl 
essence from the scales of native fishes and the experiments were 
discontinued for more important investigations. According to report 
the scales of the alewife, or river herring, sea herring, and shad are 
employed. The scales are agitated in an ammonia solution and the 
lustrous particles separated by straining the liquid through several 
cloths. The material produced is reported to be fully the equal of 
the imported essence for the manufacture of artificial pearls. The 
fishermen receive from 15 to 50 cents per pound for the scales, and 
considerable quantities are now being used for the purpose. 
NEW ENGLAND VESSEL FISHERIES, 
GENERAL STATISTICS. 
In the vessel fisheries centering at Boston and Gloucester, Mass., 
and Portland, Me., during the past year the number of trips and the 
catch were not so large as in the previous year, but there was a con- 
siderable increase in the total value of the products. There was a 
large increase in the products landed at Boston during the year, 
amounting to 14.67 per cent in quantity and 30.19 per cent in value, 
while at Gloucester tick was a decrease of 34.51 per cent in quantity 
and 31.93 per cent in value, and at Portland a decrease of 40.22 per 
cent in quantity and 8.60 per cent in value. Statistics of these 
fisheries Have been collected by the local agents and published in 
monthly bulletins showing by species and fishing grounds the quan- 
tities and values of fishery products landed by American and Cana- 
dian fishing vessels during the year at these ports. Two annual 
bulletins have been issued, one showing the catch by months and the 
other by fishing grounds. 
The fishing fleet at these ports during the calendar year 1920 
numbered 471 sail, steam, and gasoline screw vessels, including 41 
American and 3 Canadian steam trawlers. These vessels landed at 
Boston 3,342 trips, aggregating 118,558,902 pounds of fish, valued 
at $6,136,569; at Gloucester, 2,381 trips, aggregating 46,740,296 
pounds, valued at $1,460,336; and at Portland, 1,883 trips, aggre- 
