22 Report of the Board of Shell Fish Commissioners. 



in fathoms and feet, and the character of the bottom in the follow- 

 ing terms : soft, hard, sticky, rocky or grassy. 



The recorder, seated in the after part of the launch with a clock 

 before him, notifies the leadsman at the end of each 20-30 second 

 interval, by means of an electric bell, that it is time for a sounding 

 to be made, and in a sounding record book records the depth of 

 water in fathoms and feet and character of the bottom as reported 

 by the leadsman, in the following symbols: sft. (soft), stk. 

 (sticky), hrd. (hard), rky. (rocky), or grs. (grassy). 



The local assistant, operating the chain-wire apparatus from the 

 forward port side of the launch, tests the oyster ground at the end 

 of each 20-30 second interval and reports to the recorder his find- 

 ings in the following terms : barren, very scattering, scattering, 

 medium or dense. His report is given immediately following that 

 of the leadsman and is recorded in the sounding record book with 

 the initial letters of the terms used to describe the condition of th? 

 ground. 



The chain-wire apparatus as it appears in operation is shown on 

 the insert, opposite page 18 of this report. It consists in a piece of 

 heavy chain to which a stout copper wire is attached. When run- 

 ning a line of soundings the chain at the end of the wire is towed 

 over the bottom, and from the vibrations or lack of vibrations 

 on the wire the condition of the ground is inferred. The vibrations 

 are detected by holding the wire in the hand. When the drag is 

 passing over barren bottoms the chain tows smoothly and evenly 

 and no vibrations are transmitted to the wire, but when shells or 

 oysters are struck by the chain the wire is made to jerk and vibrate. 

 If the vibrations are infrequent the inference is that shells or 

 oysters are very scattering, and when the vibrations become more 

 frequent or constant, a scattering, medium or dense growth of 

 oysters is inferred. 



A small boat containing small buoys with 10-pound dumb-bells 

 for sinkers, is towed behind the launch at a distance such that it re- 

 mains above the position of the chain drag on the bottom. At points 

 on each line of soundings small buoys are cast over to mark stations 

 to be occupied and remains above the position of the chain drag on 

 the bottom. At points on each line of soundings, small buoys are 

 cast over to mark stations to be occupied and examined by the "IN- 

 VESTIGATOR" which, with an expert tongman, follows the survey 



