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DENSITIES . 
The density in the water over the different beds is given in 
the Record, Volume 1. 
The least density found, that of 1.0113 was across the 
mouth of the Pocomoke River at low water of the spring tide. 
The water of the greatest density, that of 1.0174 was taken 
from about the middle of the Sound, over the Bird, Buoy Spit, 
Muddy Marsh and Hern Island Rocks. 
The density over the beds, therefore, would be within those 
limits, the variation amounting to 0.0061. The effect of the 
tide does not appear to be invariable, as the greater densities 
were found as frequently on the ebb tide as on the flood. 
The depth of water and the prevailing winds have probably 
-a greater effect than anything else, as the density increases 
with the depth, and the prevalence of easterly or south east- 
erly winds backing the waters of the Bay up into the Sound, 
would have a like effect. 
As the variation noticeable during the space of eleven days, 
under various conditions of weather, were so small, it can 
hardly be much greater at any time, and unless much greater 
shown by the records if representing the change in salinity, 
can have but very little if any effect upon the oysters on the 
beds. By the following tables of comparison it will be seen 
that the fluctuation of density is, as in Tangier Sound, great- 
est at the head of the Sound and least at its entrance, with 
an increased fluctuation where the influence of the Messongo 
and Guilford Creeks are felt. 
On the beds above the Bird Rock the difference of density 
noticed was 0.0061. On the remainder of the beds the differ- 
ence was 0.0015, showing that there is a much smaller change 
in the density over the southern beds than over the northern. 
