The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1908-11-14

H6cOrQ6s
Great local differences in the electrifcation of
the earth are known to exist, and German engi-
neer suggests that with better knowledge it may
be possible to make mining for electricity as
profitable as digging for coal or metals. In ex-
periments in two comparatively shallow borings,
he has obtained weak currents between a small
rod of brass or iron immersed in the water Of the
pit and a similar rod buried near the surface.
He urges that contractors. mining companies
and others take up the problem, and perform
such experiments as testing the current between
a 00-foot copper cylinder at the bottom Of Dor
ing of 5000 feet or more and similar cylinder
buried in moist ground at the surface, also in
vestigating the charges to be obtained from long
iron pipes buried in the ground. 1t seems quite
possible that means may be found for charging
accumulators from earth currents, thus giving
us new source of power, light and heat.
s"s
The conclusion that light exerts pressure was
reached by Clerk Maxwell IS years ago, but
many attempts to measure the pressure gave
only doubtful results. 1t was at last shown by
Lebedew that in the tropics the suns rays have
q pressure of about three pounds per square
mile. The suns attraction upon the earth is
millions of times greater, but the attraction acts
upon the mass while the total radiation pressure
depends upon the surface exposed, so that when
matter is reduced to fine dust the radiation pres
sure may exceed the attraction. Thus it is that
the sums rays push the nebulous tail of comet
away from the denser head.
.%s
The submarine bed of the French river Adour
has been followed by Prof. Edward Hull. F. R.
s., so miles out to sea and that of the Congo he
hoe FRO cod 100 rnfloa into the ooaan
-
The electric gun, which shoots without pow
der or projectile and is already popular penny
in-the-slot toy in Paris is not designed for war
fare or hunting, but serves well for target
practice. The gun, which may be of any kind.
is mounted on special stand. while the special
target is placed 20 or rs yards or more away. The
target is perforated with 10 holes in concentric
circles and four outside holes for stray shots,
and behind each hole is an incandescent lamp in
addition to bell at the central hole. Each lamp
is fed by separate battery cell having con-
tact button in a horizontal plate in the base of
the stand. When the gun points exactly to the
bull's-eye, needle projecting downward is over
the central button. but as the guns position is
shifted the needle is moved over other buttons.
On pressing the trigger the needle is forced
downward. the contact 80 made lighting up the
lamp aimed at. The recklessness with which
these guns are Stirred" in public places arouses
indignation of the uninitiated. and there is con-
slant lodging to avoid the bullets supposed to be
flying in the air.
sSa
Recognizing uranium as the grandparent of
radium through the intermediate change to
ionium, Prof. John Jolly. in his British Associa-
ton address, showed that the transformation
has been so slow that the uranium on earth has
diminished scarcely one per cent. in 1901 900
years. Though the heaviest element known,
most of the uranium is near the earths surface.
The radium is widely scattered. and the oceans
prove to contain about 90 900 tons, derived from
the uranium brought down by rivers during the
geological ages. The heat from radium at pres
emit may be making good all that the earth is
radiating into space. This implies very long
past and future earth-life, and supports geolo-
gists in their estimates that the world is much
older than physicists have been willing to admit.
AZ
On dissecting South American boa constric-
tor, l3x feet long, Capt. Musgrave has been sur
prised to discover two rudimentary legs. only
two inches long but having hip and knee joints,
hidden under what appeared to be two distorted
scales.
AZ
Reading in bed, though common practice, is
not usually commended. The reason for disap-
proval seem to have been not clearly under
stood, though it is known that with oil lamps
there is serious risk of fire-an objection that
cannot be raised when daylight or the modern
electric light is used. DIR. Hugo Felichenfeld,
of Berlin. has undertaken recently to determine
just how'll at all-the habit is harmful. Injury
a. k<k 49, x~ooI6
light is often insufficient in position to daz-
zle, and the book is usually held too close and
seldom 80 that both eyes are used equally.
Myopia and other defects are thus caused or in
creased. Young persons, whose eyes are not
fully developed. are especially liable to be af-
fected, and it is urged that boys and girls under
eighteen should never be permitted to read in
bed. With increasing age, of course. the likeli-
hood of inducing of refraction is lessened.
Old and bed-ridden persons cannot well be de-
MED the luxury of reading in bed, and for them
the chance of harm can be made small by atten-
ton to the quality and position of the light.
**~
The bright streaks radiating from centers on
the noon-such as those from the craters Tycho
and Copernicus-have perplexed astronomers.
Fl. G.. Tomkins, British astronomer, suggests
that the rays represent extensive incrustations
of alkali left as the water evaporated from solu-
lions, and he finds like incrustations in India,
Persia and Africa. Radiations are produced on
the sides of hills, the alkali deposits on the
mountains of the Punjab, in India, being strik-
ingly similar in form to the lunar streaks.
"a
By means of an ingenious combination of the
stethoscope, microphone, monograph and gal
vadometer. a Dutch psychologist obtains pho
tographic record of the heartbeats. tits claimed
that the photograph not only shows the skilled
operator when the heart is unsound but tells
him the disease.
The topographic compass included with the
apparatus of DR.. Charcot's Antarctic expedition
is a novel instrument, Intervention of Alphonse
Berget, with which bearings can be determined
accurately at glance. A copper box contain
ing mirror perforated with peep-hole, is
mounted few inches above little compass.
On looking through the peep-hole, the mirror
shows the compassionate the precise direction of
the object in sight being indicated by the index.
80
The human mind has limitations. An astrono-
mer argues that space beyond our universe must
contain other vast universes because an absolute
void is inconceivable. But who can conceive of
an infinite space filled with an in1nity of uni
verses?
To save leg by making the veins do duty as
arteries is the remarkable feat professor of
surgery at Constantinople has attempted, with
at least temporary success. Gangrene of the
limbs as result of closing of the arteries in old
age or disease is common in the East, and ampu-
tation has been the only resource. means of
avoiding this desperate remedy has been sug-
gested by the fact that the veins are much less
affected than the arteries. Greatly alarmed by
the burning symptoms in his left leg. patient
whose right foot had been amputated on account
of gangrene appealed to the surgeon for help,
and offered to take the only chance of keeping
his leg by becoming the subject of a hitherto
untried experiment. The arteries of the leg