Figure 11. — Electrical submersible pump used for sup- 

 plying water to dredge jets. A — Submersible pump 

 discharge opening, 8-inch inside diam. B — Strainer 

 surrounding pump, mesh size approximately l-inch". 

 Any object passing through this strainer will pass 

 through pump. 



Figure 12. — Electrical submersible pump shown as 

 mounted to 48-inch clam dredge. A — 8-ihch dis- 

 charge, connected to header. B — Watertight elec- 

 trical junction. C — Header. 



of this system is that it does away with hand- 

 ling the heavy hose required for the older 

 pumping system while requiring less work to 

 gear up. 



Another recent innovation in clam gear is 

 the adai)tation of the stern trawler tyi^e ves- 

 sel to clam dredging. This is accomplished by 

 modifying the handling gear so that the dredge 

 can be hauled in over the stern of the vessel 

 (Figs. 13 and 14). This method of handling 

 the dredge, along with some constant delivery 

 system, may prove to be the most efficient meth- 

 od of harvesting the sea clam in the future. 



VESSELS 



Small dories and skiffs were first used by 

 hand rakers and tongers to collect surf clams 

 from the shallow waters along the coast. As 

 mechanical methods for harvesting were de- 

 veloped during the 1920's, other types of boats 

 were utilized to handle the new type of equip- 

 ment. Party boats, skiffs, and conventional 

 small draggers became the backbone of the 

 commercial fleet. After widespread use of the 

 hydraulic jet dredge became established, larger 

 size vessels were needed. To meet the demand, 

 regular fishing vessels were converted in order 

 to accommodate this newer and more efficient 

 method of dredging. Previously, these larger 

 boats were generally used as shrimp boats (Fig. 

 15), oyster boats, fish draggers. sardine boats, 

 and conventional military boats. The range of 

 size for these boats is from 31 to 136 ft in 

 length and from 14 to 160 gross tons. Most 

 vessels are powered by diesel engines and are 

 operated, when dredging, by two- or three-man 

 crews, dejiending upon the size of the vessel. 



SUMMARY 



The development of surf clam harvesting 

 gear is traced from early times to the present. 



During this period of time, very little devel- 

 opment work was accomplished prior to World 

 War II. After this, rather rapid strides were 

 made in development work by the surf clam 

 industry and in the past several years by the 

 Federal Government in cooperation with the 

 surf clam industry. 



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