150 THE OYSTER. 



and it is probable that the beds outside the Sound 

 would have given a much greater number at that 

 time. If we now find that the average is below this 

 number, we can safely assume that the difference is 

 entirely due to the injury which the beds have sus- 

 tained since 1879, and we can thus form some esti- 

 mate of the time which will be required for their com- 

 plete destruction. We made use of the method which 

 was employed by Winslow in his examination. A 

 dredge, a yard wide, was dragged slowly over the 

 bed until we ascertained that we were upon the oyster 

 grounds. The dredge was then emptied, lowered on 

 to the bed, and as soon as it began to take hold of the 

 bottom it was timed, and the rate of the steamer was 

 also ascertained by the ground-log. The area dredged 

 over was not the same in all cases. Where oysters 

 were abundant the steamer was stopped and time was 

 taken as soon as the dredge was full. In other cases 

 five minutes were allowed to pass and the steamer 

 was then stopped. The dredge was then hauled in, 

 and the oysters were cftunted and measured. 



This method does not give the actual number of 

 oysters upon the bottom, for the dredge does not 

 always sweep clean, and it is necessary to pass over 

 the ground several times^ to thoroughly exhaust it, 

 but results obtained in this way give the relative con- 

 dition of the bed with great accuracy. 



Whenever the contents of the dredge showed that we 

 were off the bed, or near its limits, the haul was not 

 counted, and the results therefore show the number of 

 oysters upon the beds ; not the number per yard over 

 the whole bay. 



