Report of the Board of Shell Fish Commissioners 41 



UNITS OF MEASUREMENTS. 



TIME. 



At the beginning of the survey the tongman making the 

 examinations was instructed to work ten minutes at each 

 station and his results were recorded as a fractional part of an 

 eight-hour day's labor. It was intended that the ground ex- 

 amined should be judged to be natural bar or barren bottom, 

 according to the amount of oysters it would yield per eight- 

 hour day, as based upon the amounts yielded at the places 

 examined in the fractional parts of the day spent in tonging. 



It soon became apparent, however, that there is a great 

 difference in the amount of bottom covered in ten minutes by 

 different tongmen and that the same tongman covers much 

 more bottom when the water in which he is tonging is shallow 

 than when deep. It is not. so important that the amount of 

 time spent at a station by the tongman be known as it is to 

 know how much ground is worked over. 



AREA. 



To avoid the possibility of a very considerable error in the 

 computations and conclusions concerning the condition of an 

 oyster ground as a whole, based upon the condition of the 

 areas examined, a unit of measurement of the results of the 

 work at the stations was adopted which represents a fairly 

 accurate- quantity of bottom and is independent of the amount 

 of time spent in tonging, or the ability of the tongman to work 

 rapidly. With this unit the results of each examination are 

 calculated and recorded in- terms of oysters yielded per square 

 yard. 



