Freeland tribune. (Freeland, Pa.) 1888-1921, 1899-07-13
POPULAR SClE....cE.

cOrd1Qg TO tne M .ulnS anu foclehIiho
Press, asserts that chemically pure
water is poison to tie human stomach.
upsetting some | itherto accepted
theories regarding distilled water by
the argument that il distillation the
water losses sundry salts that 1t
greedily abstracts from the animal
tissues when it is swallowed, thus
constituting protoplasmic poison. If
this view be sustained. absolutely
pure water" is more dangerous than
ordinary water impregnated with inn
purities absorbed from the atmosphere
Or collected in its flow.
Professor Torvald Kohl, OF the Cd.
der Observatory, Denmark, reports
that when the huge sunspot of Septem.
Der last was crossing the solar merid-
ian, magnificent auroral lights flashed
across the heavens, and the electric
bells in the great telegraph station at
Fredericia rang without any visible
cause. The telegraphic service in
Denmark was disturbed for hours dur
ing the auroral display. Professor
Kohl thinks that the agency of the
sun in producing the phenomena was
evident. Similar exhibitions of ''wire-
less telegraphy" between the sun and
the earth have been noted in the past.
A new form of spectroscope has re-
Gently been devised by Lord Rayleigh
in which simplicity of construction is
combined with high dispersive power.
In the new instrument ten right angled
prisms are arranged side by side in a
long tube which is filled with mix
ture of bisulphide of carbon and ben
zol in such proportions as to give the
same index of refraction as glass. The
advantages claimed for the instrument
are that it gets rid of the loss of light
by reflection, and minimiZes the effect
Of the irregularities in the glass,
while the light undergoes no refrac-
ton for that portion of the spectrum
for which the adjustment is made. On
the other hand, the arrangement is
greatly affected by temperature, as the
refraction indices of the substances
vary with any change. Professor Ray
leigh was, however, able to use the
apparatus to show on the screen the
separation of the sodium line.
More puzzling to the astronomers
than the canals of Mars is the singu-
lar doubling of some of these, or their
appearance in pairs, which appear to
be variable to different observers. An
accidental observation is brought for
ward by DR.. A. Woolsey Blackjack to
show that astigmatism may explain the
phenomena of doubling. His eyes are
affected with astigmatism, the direc.
ton in one eye being at right angles
with that in the other, and on glanc.
ing at some trees with one eye he re-
Gently noticed that all the twigs slant
ing upward to the left appeared
double, while those sloping the other
way were single. The double twigs
were like the two images seen through
a block of Iceland spar, one being
rather fainter than the other. On
changing the position of the head the
double twigs became single and the
single ones double, variation corre-
spending with what is seen in certain
canals of Mars on different nights
"hSh VIC piahCA oSCupiSS uihCiSAV
positions.
Alexander A. Lawes, civil engineer.
of Sydney, Australia, suggests plan
of mechanical fight on beating wings
as presenting advantages that tran
scend all other schemes. He believes
that the amount of power required to
operate wings and TIE difficulty in ap.
plying it are exaggerated beyond all
measure. The wings or sustainers of
the bird in fight, he urges, are held
in the outstretched position without
any exertion on its part; and many
birds. like the albatross, sustain them
selves for days at stretch. "This
constitutes its aerial support, and is
analogous to the support derived by
other animals from land and water"
The sole work done by the bird is
propulsion and elevation by the beat.
ing action of the wings. Mr.. Adams's
machine, which he does not say he
has tried, is built in conformity to
this principle, and its sails are
modelled as nearly as possible in form
and as to action with those of the
bird. The aid of an air cylinder is
further called in, through which
pressure is exerted balancing the
wings. The wings are moved by
treadles, and the authors picture OF
the aeronaut looks like a man riding
an aeriel bicycle.