Figure 7. — Classic 40-inch hydraulic jet dredge used by the majority of fishing vessels operating along 

 the coast of New Jersey and Maryland during the late 1950's and up to the present time. Note that 

 the dredge itself is all enclosed except for the bottom and forward section of its top. Loose aprons 

 built out of rings are used to enclose the space between the dredge and sled to prevent loss of clams 

 between the two units. In addition, chain attachments are used between the two units for towing 

 purposes. Attached to the sled is the chain bag built of 3-inch scallop rings and connectors. This 

 dredge is equipped with a straight edge knife. Many dredges use a V-shaped knife that floats on 

 springs and digs into the bottom only after the water to the jets is turned on. In use of spring-mount- 

 ed blades, the knife settles into a trough which is jetted out by the water. Dredges with this type 

 of blade also use a V-shaped manifold as compared to the straight manifold shown hei'e. The clam 

 jetting hose shown has been built especially for clam jetting and has a 5-inch inside diam. 



