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Section No. 4 was across the middle of Pocomoke Sound, 
that the influence of Guilford and Messongo Creeks might he 
known. 
Section No. 5 was above the natural beds of Pocomoke 
Sound and across the mouth of the Pocomoke River. 
Stations were selected on these sections in such a manner 
as to obtain specimens of the water that passed over the beds, 
and the specimens were taken by means of the drop water 
cylinders at every two fathoms of depth. 
As soon as possible after securing them they were tested 
with the hydrometer. The results are tabulated in the “ Re- 
cord of Densities” and curves showing the various changes 
accompanying this report. 
All densities are reduced to a standard temperature of 60° 
Fah., and 1,000 represents the density of distilled water. 
In studying these curves, it must be remembered that only 
their variations are of particular importance. The absolute 
density is not so much so, except for comparison with that of 
other localities, but the variations in density are important, if 
by them we can account for the failure either of the propaga- 
tion or attachment of the young oysters. 
The curves will show certain irregularities due to either the 
variations in depth, or because the tide having changed from 
flood to ebb, or the reverse, on one side of the Sound at a 
time differing from that on the other. 
As will be seen, however, the greatest variations in each 
month are in Tangier Sound, on the eastern side, where the 
influence of the rivers is felt to greatest extent. 
In Pocomoke Sound the greatest variations appear to be on 
the western side, and I assign as a reason for this that the in- 
fluence of Guilford and Messongo Creeks is of small import- 
ance compared with that of the Pocomoke River, the current 
from which sweeps along the northern and western parts of 
the Sound. 
The curves show that the variation is very slight, except on 
the September sections. 
The second series of curves, those showing the monthly 
changes of mean densities, indicate that the maximum change 
