Evening star. [volume] (Washington, D.C.) 1854-1972, 1898-04-09
UNSTABLE QUlcKSANDS
Explanation Of Ono Of Natures Most Oufi-
GUS Phenomena.
In Every Case an Upward Current Of
Water II Necessary How
They Are Formed.
From Invention.

From In, ention.
Very little is known by the general public
about quicksand, and that little is usually
obtained from novels. Such information is
usually wrong, being composed Of pinch
of truth and handful Of fiction. The SEN
sational novel goes even SO far as to give
to quicksand some attributes that belong
only to living creatures. No ordinary OBJ
server could distinguish quicksand from
any other, II it were dried; and If he wish
ed to restore its fatal property artifcially,
he would in all probability fail. Suppose
he fills bucket with water; 1t does not in
consequence become mobile. If he drains
the water OF from the bottom, the sand
will be found wedged firmly In place, and
If the water be measured 1t will be found
to equal 80 per cent of the bulk Of the
sand, or about 20 per cent Of its weight.
From this we may infer that a cubic foot
of dry sand weighs nearly ninety-four
pounds
This. for sand, Is a very light weight,
for there are other qualities Of sand which
weigh as much as Ill pounds. Quicksand,
when examined under a microscope. will be
seen to have rounded corners like river
sand, as distinguished from angular or
sharp sand, which will pack more solidly
than the other. 1t Is quicksand that is
used in the hour-glass and in the smaller
egg-boiler, partly because Of its fneness
and partly because It does not obscure the
inner surface OF the glass by scratching.
The lightness of Quicksand is the quality
which will lead US most surely to the cause
of its reputation, and to illustrate this the
bucketful of sand must be loaded with wa
ter from below, and made to overflow very
slowly. The upward current will be found
to loosen the sand and to raise the surface
very slightly, separating and lubricating
the particles so that they are easily dis
placed.
Curious Qualities.
The bucket now contains quicksand. and
this sand from the support 1t receives from
the water has its weight or supporting
power reduced. In the dry state it weighed
nearly ninety-four pounds. but II weighed
in the water it Is reduced to thirty-two and
one-half pounds, and its mobility prevents
any animal from walking on 1t. The mix
ture of sand and water weighs quite IL
pounds per cubic foot, or nearly twice the
weight Of water, and bulk for bulk nearly
twice the weight Of a man; but 1t Is too
thick to swim in, and the person engulfed
would soon be too exhausted to escape. He
would probably die Of suffocatfon II not
drowned by an advance tide, for quick
sands are found mostly within the infiu-
ence of tides. He would not be swallowed
by the quicksand, because 1t Is SO much
heavier than his body.
\ZuiCkSdHOS require III ILL cases All up
Ward current which is not quick enough
to form what is called q spring or foun-
tain. 1t may be formed in two ways-in
tidal rivers and on the shores Of tidal seas
the rising tide may saturate porous
stratum of ground below high water mark,
and when the tide falls the return current
is established through the same porous
(sandy) ground with sufficient velocity to
loosen the sand as above described. This
sand as soon as the rising tide reverses
the current ceases to BE- quick" The 9TH
er case Is that when slow current OF
fresh water finds an exit through a surface
Of sand above or below water. This is a
permanent quicksand. Any sand and al
most any material might have the quality
of qu!cksand impaired to it by means of a
suitable current.
Coal Is separated from shale in an up
current of water, SO regulated that the
coal Is made to float while the shale falls
to the bottom and heavy iron tools have
been carried to the surface by the sudden
discharge of artesian wells Quicksands
that are encountered during the sinking of
wells and foundations are all due to the in
hux of water when the work gets below
Spring level" or the level Of water in the
ground. The sand, being deprived of the
support Of the excavated part, Is pushed
from behind by the water current flowing
in from all sides.