80 Power of Soils to Absorb Moisture. 
It is generally observed that stiff clay soils do not stand a 
drought as ^yell as sandy soils. This would constitute an appa- 
rent exception to their absorbing moisture with much greater 
energy. The reason is obvious. The amount of moisture equal 
quantities of the same soil wMll absorb in a given time will be 
proportional to the extent of surface exposed. The parts of a stiff 
clay soil adhere together with so much tenacity that in drying 
they cake, crack open and become more compact, shutting the air 
from all parts except those which are immediately contiguous to 
the surface, while in a sandy, or any loose, porous soil, every par- 
ticle may be said to be in contact with, and surrounded by the 
atmosphere. 
The more we do, the more we are convinced of the practical 
utility of the absorbing power of soils. If we had not tested a 
large number of them, the analyses of which had been previously 
made, we should not at this time have spoken with as much con- 
fidence. 
Quick Sand. 
We do not intend to say much on this subject, for the reason, 
that we have not much to offer. The name is, and has been ap- 
plied indifferently to all such masses of earth as do, when dug in- 
to or agitated in any way, assume a partially fluid form. The ap- 
plication we think has been correct — for we do not believe — we 
know — that this partially fluid state is not confined to particular 
beds of sand, which — as is, and has been, the prevailing opinion 
among people generally — possess some peculiar .chemical or me- 
chanical properties; or both, by virtue of which they have within 
themselves a power of flowing when disturbed, which distinguishes 
them from all other masses of earth. This property, we believe, 
not only extends to all beds of sand, but is common to all soils 
when subjected to certain conditions. All that is necessary in 
order to have them assume this peculiar form is that they should 
be influenced and controlled by the proper circumstances. 
Beds of sand when subjected to these circumstances or condi- 
tions are much more difficult to control than ordinary clay, marl 
