The citizen. (Frederick City, Md.) 1895-1923, 1897-08-20
written for the citizen.J

OulutIlAllus
TALLY to oxygen as the pressure in
creases, although the change is not
complete even at high pressure. 1t is
found that the proportion of ozone in
the atmosphere at the earth's surface
should he about one volume in 1000,
while the actual proportion is about
one volume in million-a difference
between theory and fact that is &C.
counted for by the chemical activity OF
the ozone, which causes it to unite
readily with metals. These deductions
explain the current view that the air
of elevated regions is highly charged
with ozone and show also that there
must be sufficient ozone in the atmos-
phere to give the sky much Of its blue
ness.
In experiments by Mr.. Guy Oliver
Harrison, of Liverpool, England, the
sensitiveuess of the retina to y rays
was evident after the eyes nad been in
The Crookes tube was placed under "A
table of one-inch deal, and the rays
were perceived as a faint illumination
of the Ietina on bringing the head
above the table, while the shadow of a
piece of metal could be distinguished
aud it was even possible to make out
letters about "a quarter of an inch long
in sheet of lead. 1t made little differ
ence whether the eyelids were closed
or open.
From many years observations, the
Director of the National Observatory
at Athens finds that the absolute eX-
tremes of temperature vary from 1852
TO 1862, n range of $50. Rain falls on
9s days in the year. the annual amount
being l6 inches. In 1894 Athens had
2.527 hours of sunshine, while in some
seasons the sun Is unclouded for a
month at "A time.
The records of IS years show that
tornadoes have width of 10 to l0,560
feet. length of track of 800 yards to
900 miles, and velocity of progression
of ! to 100 miles an hour.
Diseases have their local habitations,
saws the London Saturday RcricU.
Some, like tropical animals and plants,
live only in the tropics; some, Ike
consumption, are gradually spreading
over the whole earth; others, like lep-
rosy and smallpox, are gradually be-
coming limited III their distribution,
and may actually be tending toward
extinction. Again, there are regions
to which diseases have never reached.
AOn the Mmmits Of high mountains
and in thScircum- polar snowtields, the
earth and air and water are as barren
of the microbes of disease as they are
of animal life. Without question, if
Nansen and his companions had been
exposed TO the same hardships and the
same unsanitary conditions in these
islands, the lowered vitality of their
bodies certainly would have been I'M
able to resist the continual lombard
ment of germs to which we are all sub.
iected. In a country like Britain,
thicklv populated for many centuries,
and with the freest circulation of pop
ulation. it cannot be doubted that
every ward of surface contains the
and the native of some newer land,
brought over here, falls victim to our
plague-stricken soil. BY generations OF
a destructive elimination we have be-
come highly resistant to our native
diseases, Just as the Gold Coast natives
are less susceptible than we are to their
own local diseases. But we are not
fully protected, and cancer and con-
sumption-two Of our common scOurges
still take "A large annual toll. III may
be assumed that both are due to micro
organisms, the microbe OF consump-
ton being well known, that of cancer
being as yet only suspected. Probably
no inhabitant of Britain escapes intec-
ton by the cancer organism; certainly
none escape infection by the microbe
of tuburcle Most of Us, fortunately,
resist the intruders, and are unaffected
by the disease.
A new study of human development
has been published by a German au-
thor. +. Hahn. He maintains that
primitive man was an omnivOrous
feeder upon whatever could be picked
up. aud that he then became severally
a hunter fisher, planter and a
herder. but that these modes of gain
ing a livelihood were not taken up
successfully as an evolutionary series.
He finds barley to have been the first
cereal. and wheat the latest. Cattle
were first domesticated as draught ami
mails, especially TO draw the pillow, and
their mix was not used as food until
long aiterward. The wagon is assigned
II tch .I tr, Ia. Na
had four wheels derived from spindle
whorls, and to have first transported
efiigies of the goddess of fertility.
The diving-cabin, or submarine
traveller" of NJ. Piatsi del Pozzo, which
has been used in the Seine and is be-
leved to be suitable for deep sea eXplor-
alton, Is ten feet in diameter and
weighs ten tons. II is moved by three
screws and helm worked by electric
ity. The cabin, which is entered
through man-hole, is claimed to have
an air-supply sufficient for As hours for
four persons, is lighted by electricity,
and is provided with levers or hand
spikes Tor working the shovels, picks,
graphing irons, ETC., on the outside of
the machine. COnical tubes provided
with lenses give views of the ground
and exterior objects in all directions.
Communication with land or boat
can be kept up through a telephone,
and even if the cable supporting the
apparatus should break, it is only nee
essary to touch a lever to cause two
tanks containing ballast to overturn,
when the globe will at once rise to the
top of the water,