64 XJ. S. BUREAU OF FISHERIES. 



pushed along with one hand and affords a means of balance while 

 the operator stoops over to disembed the clams. When a boat be- 

 comes loaded, it is poled or pushed to shore, where the clams are 

 cached in shallow water to await the arrival of a " run boat," which 

 brings them to the canneries. During the course of a day a hand 

 digger makes several trips to shore with clams. 



Dredging is by far the most efficient method of procuring clams. 

 The dredge used in the Key West region is of a unique type, one that 

 is not used in any other part of the world. The first dredge was 

 operated about 1905, but some years afterwards it was destroyed 

 by fire. Later a new dredge was built and was still in use at the time 

 of this writing. In September, 1922, a second dredge was put in 

 operation to supply the increasing demands of the canneries. x\fter 

 the second dredge began working hand digging ceased entirely, for 

 the two dredges have been able to dig sufficient clams to supply all 

 demands. The new dredge has not been observed by the author, 

 but it is understood that aside from a few improvements it was built 

 on the same general plan as the old one, a description of which 

 follows. 



In general appearance the dredge resembles a houseboat. It is 

 about 90 feet long and 20 feet wide and has two stories. Dividing 

 it into thirds, the digger is situated in the middle, the machinery 

 and tool room on one end and storage space for the clams on the 

 other end. The second story is devoted to sleeping quarters and 

 mess room. 



The machinery is gasoline driven, a 36-horsepower engine being 

 used, and heavy chain belts drive the various wheels and gears. The 

 digger itself is a rather powerful machine. It has 10 rows of teeth, 

 each row being separated by a distance of about 2 feet. The teeth are 

 detachable in series of two and are attached by bolts to heavy strap 

 iron, 18 teeth forming a complete row. The ends of the strap iron 

 are attached to the chain belt, which revolves the digger. Each 

 tooth when new is 6 inches long and curved, and a complete series 

 of 18 digs an area about 6 feet in width. 



The digging apparatus, which resembles a thick rectangular 

 figure rounded on each end where the cogwheels are located, is set 

 at an angle, allowing one row of teeth to dig at a time. The posiiion 

 of the digger is regulated to the depth of water by two heavy 

 counterweights, which are placed at, the extreme end of the dredge. 

 The clams, soil, etc., are carried up by the curved teeth, and on the 

 downward turn they are deposited on a moving wooden escalator 

 or conveyor, which is provided with raised strips of wood at con- 

 venient intervals to prevent the clams from rolling back into the 

 water. This escalator is an unique appliance — it might better be 

 called a wooden belt conveyor. That part of the conveyor upon 

 which the clams are deposited is under water, so that when the 

 clams reach the pickers they are partially cleansed of mud. 



At the top of the wooden conveyor two or more men pick the 

 live clams, which are thrown into baskets. One man is employed 

 to remove the filled baskets and to replace them with empty ones, 

 as the pickers can not move from their positions without missing 

 some clams, which would be carried over and into the water by the 

 conveyor on its downward turn. When three baskets have been 



