The Washington herald., 1913-07-27

has been washed in II. Lead and some
of the other minerals are not SO easily
distinguished, and are not quite Sc
health.ul especially IL they exist in very
large quantities.
probably the most apparent are the
caustics, the presence of which is al
ways indicated by the hardness OF
water. Lime, which dissolves in water
as it passes through the calcium de.
posits Of the earth, is most familiar OF
them. Although 1t is hardly percep-
tible to taste, and, unless it exists In
great quantities, is not apt to be in.
a nuisance for laundry and industrial
purposes. In the laundry 1t causes
much waste in soap, owing to the free.
dom with which 1t mixes with the al
kali. thereby lessening the lather and
making the work longer and more
tedious. In industrial pursuits it 1,
the ruination of any metal work with
which 1t comes in contact. 1t scales
the insides of boilers, which require
more heat and more fuel, and in a com.
parat.vely short times eats through
them, shortening the natural life Of Q
boiler at least one-third.
Waters containing such solutions
have been avoided from the beginning
SClenCc, AowCNcls mas dl idS
found a means of destroying in a great
part their nature, thus rendering them
as At as any other normal water fol-
use by humanity. Chemists in all
lands have worked many years on this
problem, and several of them have wor
great success. particularly DR.. Clark
a noted English scientist, who. by ex-
periments and soap tests, finally DEM
onstrated that lime can be removed
from water by the force of its own re.
action or by passing hard chalk wateI
through a prepared solution of lime
water which gathers and precipitates
the lime in the raw water and sends
it to the bottom. In this manner near.
ly 80 per cent of the chalk can be re.
moved, which really amounts to moth.
ing more than removing lime by the
use Of lime. Once the lime Is freed
from the solution and floats about In
the water It is easily removed by filter
ing or straining.
Anclents Were Ignorant.
''The knowledge Of the ancients on sub.
jects Of this nature was, Of course very
limited. but at very early date they
were not in total ignorance of all mat.
tiers relating to water and water sup.
plies. With the advance of mechanical
science, their wells progressed in mum.
bers, depth, and architecture. and some
of them are the finest specimens Of Their
handicraft. Joseph's well at Cairo, per
haps, exhibits in the highest degree the
constructive skill of the prehistoric
Egyptian. It consists of two shafts sunk
to a depth OF nearly 800 feet II solid
rock. Buckets on endless chains ,onsti.
tute its lifts, those on the lower shaft
being operated by hand. A spira. for
the passage Of the mules winds aoout
the well from the surface to the lower
level. The Chinese sunk shafts Of this
nature to a depth Of nearly i.soo feet.
Before wells attained anywhere near
such proportions the early people began
to realize their inadeQuacy to supply the
vast amount Of water needed in all sea-
sons. Consequently, reservoirs came into
use to collect water from rains during
wet periods in SUFFICIENT quantity to tide
them over the dry season. In Assyria,
Egypt. and India, and other places where
civilization existed. reservoirs OF unusual
dimensions were constructed. Jerusalem
boasted Of several underground cisterna