Evening times-Republican. [volume] (Marshalltown, Iowa) 1890-1923, 1903-07-27

more than passing attention. Modern
investigations along this line nave
shown that, for example. the dastlnc-
ton which used to be drawn between
deep aud shallow wells IS Of but very
limited value. Deep wells, according TO
the definition. are those which pass
thru an impervious stratum and draw
water from a deeper layer beneath, but
this can only happen In geological pa
sin, and geological basins are few and
far between. Whenever these arteslah
wells are possible they generally yleld
a very pure water, but the nature OF the
strata thru which they pass must also
be considered In a limestone region.
for instance, wells are dangerous on
account of the many underground
seams Which transmit water with great
facility. When water passes thru THESE
caves it is not benefited by the natural
filte.Ing properties of the soil, and IN
lection in this way may travel great
distance. A limestone country is gen.
orally honeycombed by caverns of vast
extent.
Another formation worthy of men
ton is the clay. These beds are al
most impervious to water. ana what
does pass thru short distance Is gen.
orally filtered. Many we'll owes us
freedom from disease producing germs
to the fact that it is surrounded by a
stratum of clay. Gravel, on the other
hand, presents directly opposite quail
ties. The same property which makes a
gravel bed good for building purposes.
/. e. because drainage is good ana a
4 To-, t.. tnsr ffiah III
very hard for wells. for 1t is so porous
that there can be hardly any hope Oh us
yielding an uncontaminated water, II
there is any means OF contamination
within a reasonable distance.
such are some of the considerations
which arise when one is In search OF
good well water, but irrespective OF
any of these. and without care or study.
wells have been dug everywhere In your
city and most all of them are polluted
The question is at once asked, Gan
ANYTHING be done with these old wells
whereby they may be rendered SAFE as
IL source of drinking water? 1t at al.
possible it would be best to completely
eliminate them and obtain some other
supply. When this not feasible the wei
liz not too grossly polluted. may be rem
oered more or less safe by a method
devised by DR.. Koch.
Suppose that we have one of these
wells that yields polluted water. 10
begin with we take out the pump, Il
there is one, and pour in sand until IL
reaches within a foot or so OF the low
est water level, the lowest level OF the
ground water generally occurs at the
end of dry, hot summer. for this rea-
son such a time should be selected for
the application of this method. we
now place in the center of the well an
| iron tube three or four inches in di-
ameter. with it's lower end extended and
| perforated This end of the tube rests
on the sand. and while 1t is held IN
place. a bushel or two of fine gravel is
thrown in Immediately surrounding 1t
and the well is then completely nilea
| with sand. II now pump is attacneo
\ to the tube, we have very good tupe
well which differs from an ordinary one
| In that 1t Is surrounded by q hlterina
layer Of sand. Probably this is the hes'
that can be done with dug well.
1.-The next question to be answered
| is: How may we'll be constructed, II
at ALL in order to meet modern sanitary
requirements" While We must admit
that this is hard to do, In the face
Of probable groundwater contamina-
ton. still, under certain conditions
| there are certain kinds of wells whlef
seem to give satisfaction. For exam
pie, in some places, deep artesian wells
will yield the best possible results, but
this. Of course, is only over regions II
which the strata are approximately
horizontal. The ordinary tube well car
not be recommended any more than
dug well, filed with sand after DR.
Koch's method, altho either would be
far safer than any ordinary boring
This is true not only for regions OF
dislocated strata, but also for beds d
limestone, sandstone or loose rock OF
any kind The fact is that perfect
well can never be constructed by any
| given rule. A careful study of the
locality and the nature and dip of the
strata must be made IL we would have
| pure water. and even then 1t is hard
to get it unpolluted from wells of any
kind except, perhaps, artesian.
CHARLES II. HOFFMAN.