Manchester Democrat. [volume] (Manchester, Iowa) 1875-1930, 1908-08-05
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IN the absence Of other water steriliza.
tion DR.. Riegel Of the Austrian Army
finds citric acid effective. In 4 shall
low vessel In sunshine Cloth Of citric
acid killed cholera germs In I'VE min
utes and the typhus In an hour and a
half.
The singular phenomenon Of hard
steel being cut by rapidly revolving
disc Of soft steel has been somewhat
puzEling. A microscopic examination
BY an English engineer, B. w. Har-
bord, has now shown that the metal
acted upon IL heated nearly or quite to
the melting point Of steel, but only at
the point Of contact with the disc.
At the recent meeting Of the Ameri-
can Association for the Advancement
Of Science, in Chicago. attention was
called to the interesting fact that the
work on the Panama Canal is changing
biological conditions in Panama, and
that Its completion will enable the
fresh-water fauna Of the Atlantic and
Pacifce slopes to intermingle. I'm
doubtedly, many marine animals will
pass from one ocean to tho other. Thus
a permanent change Of conditions will
be brought about, which may or may.
not possess much practical Importance I
but Its scientific interest is very great.
In view Of these facts, the association
resolved to urge upon Congress the ne
cessity Of an immediate biological sur
vey Of the Panama Canal zone.
The question of the possibility Of life
on the planet Mars continues to excite
wide interest. Recently DR.. Alfred
Russell Wallace has combated Prof.
Percival Lowell's conclusion that such
life exists. Among the objections urged.
against the theory of the habitability.
Of Mars are the rarity Of Its atmos-
phere and the probably excessive frigid.
ity OF its climate. Or. !. ". Evans 81.
the Imperial Institute, London, re-
marks. In regard to this point. that the
influence Of carbonic acid on atmos-
pheric temperature seems not to have
been sufficiently considered. A slight
variation in the amount of this constit-
uent has an important effect upon the
retention Of heat. With a relatively
large proportion Of carbonic acid, the
atmospheric temperature rises. Dr..
Evans suggests. as an interesting specu-
lation, that such condition may exist
upon Mars. and he thinks that the
quantity of carbonic acid required to
make the temperature endurable would
not be 30 great as to be Injurious to
animal life. Plant life would flourish
luxuriantly in 1t.
Architects find no more difficult prob
lem than that presented by the acous-
tics Of lecture and concert halls. The
subject has been Investigated by Prof.
Wallace g. Sabine of Harvard, who
presents some interesting conclusions
The acoustic properties of hall de-
pend upon two variables-the form and
the materials. The essential features
of the materials are their absorbing
and reflective powers. The Fogg Art
Museum lecture hall was modelled after
: E b Z
the Sanders Theater In Cambridge, but
failed to reproduce Its excellent acous.
tic properties. The reverberation Of
sound lasted b.62 seconds-an intoler-
able length. By putting Sanders Thea
ter cushions on the seats, floor and
part of the wall, the reverberation pc
Rod was reduced to LA seconds. An
open window is an absorbent of sound.
An audience absorbs. per square meter,
.94 as much as an open window. An
isolated woman in the auditorium abb
sorbed "a as much as window, and
an isolated man .4S, apparently a trib-
ute to the superior excellence Of female
apparel. Hair felt on the wall alb
sorbed. per square meter. 10 as much
as window.