1 8 Report of the Board of Shell Fish Commissioners. 



cal and biographical investigations 1 have been purchased by the 

 Commission. 



ORGANIZATION. 



The organization of the party for hydrographic field work when 

 fully completed is as follows : 2 



1 Hydrographic Engineer. 2 Oarsmen. 



2 Asst. Hydrographic Engineers. 1 Boatswain (houseboat). 



1 Draftsman. 1 Nightwatchman (houseboat). 



1 Clerk (on houseboat). 1 Coxswain (Investigator). 



# 1 Recorder. 1 Machinist (Investigator). 



'l Leadsman. 1 Tide Observer. 



1 Local Assistant. 2 Cooks. 



1 Expert Tongman. 2 Waiters. 



Day laborers for buoy construction and oarsmen have been hired 

 as the exigencies of the work required. 



METHODS. 



The methods employed by the Commission in making the hydro- 

 graphic survey of the oyster grounds of Maryland, with slight 

 modifications, are the same as those used by the United States 

 Bureau of Fisheries in conducting surveys of oyster grounds in 

 other States, 



and by the Coast and Geodetic Survey in making hydrographic 

 surveys. 



The approximate position of an oyster ground having been 

 pointed out by the local assistant, a zigzag or parallel series of lines 

 of soundings is run over it by the engineers and their assistants in 

 the launch "CANVASBACK," in order to ascertain its exact limits, 

 the depth of water over it and the general condition of the bottom. 



A chart, known as a "boat sheet" (a copy of a polyconic projec- 

 tion) showing the shore line of the waters of the section being sur 

 veyed and the plotted positions of the triangulation stations above 

 which signals have been erected, is spread on a chart board in the 

 launch before the engineers and upon this boat sheet the positions of 

 the launch at the end of intervals of two or three minutes while 



i The apparatus used in ascertaining the density of the water over the oyster 

 grounds is the property of the United States Coast and Geodetic Survey. 



2 Changes having been made in the personnel of the party as the survey 

 progressed from one section of the State to another, the names of employees 

 are omitted. 



