"Figure 46. Diagram of the method used in experimental hatching of quahaug eggs and rearing of the young larvae at the Wellfleet laboratory.  It represents a cross-section of the laboratory, showing a small 1 ½ horse power gasoline engine (B), connected by a belt pump (C), by which salt water is forced from below into a tank (A) situated near the roof.  The laboratory is located on a wharf over the water, which enables salt water to be obtained directly from beneath the floor.  The inlet of the pump is guarded by a strainer (H), which prevents seaweed entering the pipe.  From the tank the salt water is conducted through the laboratory by a large pipe set with small petcocks.  From these petcocks pieces of rubber tubing (F) lead to the hatching tubes (E), which consist of half barrels fitted with sand filters (D).  The tubes are placed over a sink (G) which carries off the filtered water.  By this arrangement a continuous flow of water is established through the hatching tanks."

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