22 FISHERY INDUSTRIES OF THE UNITED STATES. 



glass spheres is coated with this essence and the cavity filled with a 

 hard white wax. 



In the past the best scales for the-purpose were obtained from one 

 of the cyprinid fishes of Europe. Tlie siipply of pearl essence was 

 curtailed by the outbreak of the Great War, and m 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 iishes. Promising samples, although 

 never free from color, were made from the scales of tne alewife, or 

 river herring. iVfter treating the scales with ammonia the lustrous 

 particles were separated out by centrifugation. vSamples submitted 

 to American representatives of Parisian pearl manufacturers were 

 pronounced oft' 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 there 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- 



