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Scientific Memoirs by

     During this period 1,772 c.c. of water had disappeared from the cavity in
the soil and 75 c.c. from the glass vessel due to evaporation, leaving a loss of
1,697 c.c. to be credited to the permeability of the soil. The entire cubic
capacity of the block of soil minus the cavity was 1,635.5 c.c., and hence during
the period a bulk of water had disappeared from the cavity due to percolation
greater than the bulk of the entire block into which it was absorbed. The
results moreover, as in the previous case, by no means represent the total
absorptive power of the mass of soil for the period, as the cavity was almost
always empty for a considerable period daily and on some occasions remained so
for entire diurnal periods.

     A third experiment was now tried with the same mass of soil and only differ-
ing from the previous one in that a glass cylinder open at both ends was fitted
accurately into the interior of the cavity, any small interspaces between the
glass and soil being filled with firmly rammed material, so as to secure accurate
contact everywhere. The cavity in this case thus differed from those in the
previous ones in having impermeable walls, so that water could only come into
contact with the soil of the floor. The experiment lasted from the 1st to the
29th June with the following results:—