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The number of oysters would then, on a limited bed, steadily 
increase, as long as there was sufficient room and food supplied 
them, until they had reached their limit, a rather indefinable one 
in that direction, the quality of the oysters not being taken 
into consideration. Having reached that point, the number 
of oysters would to all intents remain the same as long as the 
conditions under which they had previously lived were not 
changed. To cause, then, either an increase or diminution of 
the number of oysters or size of the bed, a new factor must 
be brought in, when, all conditions being changed, the life of 
the animals begins anew and progresses differently. As there 
can be no doubt that both the beds and oysters of Tangier and 
Pocomoke Sounds have changed greatly in character since 
their first discovery, in accounting for that change it is neces- 
sary to discover the new factor or factors that have been intro- 
duced, and that have been instrumental in effecting it. Briefly, 
the change in the beds has been a material expansion of their 
limits and a material diminution of the number of oysters upon 
them, and therefore the causes for such changes must be sought 
among such as it is known would produce like effects. 
Disregarding for the present the agency of man in the mat- 
ter, the question is what natural cause or causes would both 
expand the beds and diminish the number of oysters? A 
bed is extended naturally by the drifting spat or “ young 
brood ” attaching themselves to any clean, hard and moder- 
ately rough substance contiguous to the bed. The locomo- 
tive powers of the u spat ” exist for but a short time and, 
except when assisted by the current, they can only move a 
short distance, and unless some suitable object soon presents 
itself for their attachment they will sink into the soft bottoms 
and die. The principal expansion of the beds so far as could 
be effected by nature must, however, have been accomplished 
long ago, the beds being surrounded originally, and indeed 
at present, by soft bottoms of a character which would be 
most destructive to the “ brood,” unless some substance was 
interposed between it and them for their reception. Natural 
expansion can only be achieved to any extent in the manner 
described, and though probably there is, and has been, a slow 
