The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1900-10-13
O0rrsspondence Baltimore County Union.
SCIENTIFIC MIS- CELLANY.

OOAGIN 1T ~ MI ObAA1A4NA
Heat-Stroke and Sun Observation-Disclosures
from the Deep Sea-A Mechanical Life
Rsstorer-A Piston Engine Without a
Crank-Mystery of Becquerel Rays
Russian Bricks-A Useful Cement-In-
candescent Air From Compression
Simplifed Living Pictures.
The discovery of distinction between heat
stroke and sun-stroke is claimed by DR.. Nous
soier, French naval surgeon, who believes
that considerable saving of life should follow.
at-stroke, he afirms, results from prolonged
exposure of the whole body to moist or dry
heat exceeding 104o F., and its i'll effects are due
-~to-the action OF the superheated blood. Sum
stroke instead of being caused by high tempera-
ture, is induced by chemical rays from intense
sunlight falling on the Uranium. 1t can occur
only in the tropics, and the immunity of blacks
is explained by the fact that dark skin or
other substance almost completely stops the
passage of chemical rays.
-
The breeding of the common eel is one of the
interesting questions settled by naturalists
within the last few years. The young are not
at all eel-like. and were called Leptocephali,
says Prof. Ray Lancaster, until ten or twelve
years ago, when specimen in an aquarium on
the coast of brittany gradually developed into
q conger eel. The first inference that the Lep-
tocephali were abnormal eel progeny has now
been proven to be erroneous, the various kinds
having been shown to be the normal young of
the various eels The breeding place has been
traced finally to the sea, where the eggs are
laid and hatched in depths as great as 500
fathoms.
Restoration to life after hours of apparent
death is now known to be possible in cases of
persons taken from the water or from suffoca-
ting gases. In 1898 an apparently drowned boy
of sixteen was resusicated by tongue traction
continued for three hours. and to make it easier
to persist in lfe-saving effort for hours in SINH
lar cases, DIR. Laborde, French physician, has
devised mechanical tongue tractor. driven by
an electric motor.
A Leyden jar on balance is said to become
perceptibly heavier on being charged, and Dull
ca, a French physicist, finds that the apparent
change in weight is smaller before rain. thus
making it possible to predict the weather by a
Leyden jar and balance.
"a
One of the most remarkable of the attempts
at steam-engine improvement that have fol-
lowed the advent of the steam turbine is the
'crankless' engine of Ljungstrom, Swedish
engineer. In this engine a pulley is mounted
at one end of shaft, and to the other end is
attached casting in the form of four radical
cylinders, these cylinders revolving with the
shaft in a closed chamber. Each cylinder is
fitted with a hollow cylindrical piston. whose
outer end carries roller which is pressed by
centrifugal force against stationary ellipti-
cal track formed by the outside casing. The
steam supply comes through a pipe enter
ing the casing opposite the shaft, and screwed
to the supply pipe is stationary valve. which
is cylinder fitting into hole in the center of
the rotating casting, and having two long slots
or ports connecting with the supply pipe and
two connecting with an exhaust pipe. Each of
the four cylinders has similar long slot at its
inner end. As the pistOns, following the ellipti-
cal track, move outward, steam enters through
the valve and cylinder ports, and it passes out
through the exhaust ports of the valve as the
pistons are forced inward, the rotation being
kent up by the side thrust of the pistons when
forced by the steam pressure against the out
ward going curves of the track. A governor
inside the pulley acts on the steam supply,
while moving handle quickly reverses the en-
CINE by changing the radical position of the
valve ports and permitting steam to enter the
cylinders when the pistons are moving inward.
This engine is comparable with the steam tur-
bine in its extraordinary power and efficiency,
and its small size.
How to account for the rays emitted by ra-
dunn in the dark has been puzzle to physicists,
for it could not be supposed that any substance
could emit radiations having energy without
loss of weight or the introduction of work from
an outside source. The solution of the prob
lem now offered is scarcely less bewildering.
The quantity of this energy has been measured,
and Becquerel calculates that it could be &C
counted for by assuming loss of material OF
one milligram per square centimeter in thou
sand million years-that is, the consumption OF
tenth of grain on a square inch in 1OOOO,OOO
centuries would keep alive this mysterious ac-
tivity.
It is pointed out that a small bronze green
humming-bird of the island of st. Vincent has
not been seen since the w. Indian hurricane OF
September, 1898, and it is asked whether the
storm has completely exterminated this species.
.*s
A novel and rapid process of making bricks,
the invention of w. Olschewsky, Russian en-
gineer, is being worked at Coswig, Germany.
Varying proportions of Stacked lime, ranging
from to 10 per cent of the total mixture, are
used with sand, and the mixture is pressed into
bricks These are exposed in closed chamber
for IL hours to steam at pressure of 10Opounds
per square inch. The finished bricks, which are
porous and absorb ID per cent. of their volume
of water on immersion, have a specific gravity
of 1.Ss and crushing strength of go tons per
square foot.
This is a German method of making 'Shio
Liao.r famous cement used by the Chinese to
unite gypsum. porcelain, marble, stones and
stoneware. The materials are 81 parts of
Stacked powdered lime, parts of powdered
alum and 40 parts of fresh, well-stained blood (;
and these are stirred until a well-mixed
mass of the consistency of somewhat stiff
saIye is obtained. When sufficiently thinned,
this cement becomes a durable waterproof
-paint of varied uses. Two or three coats
make cardboard covers as hard as wood. it may
be used for painting houses, and it gives barrels
an oil-tight glaze.
1t appears from an observation by Heise that
even fiameless explosives may set fire to gases in
mines. A compression of 200 atmospheres would
raisa the temperature of air to 1902 c., and, as
explosives in bore holes can exert a pressure OF
1000 to 5000 atmosphcres, the heat of compress
sion would be quite sufficient to ignite infiam-
mable gases in the neighborhood. Aphotograph
described by Oscar Guttmann is held to confirm
this theory. 1t shows a flash at the meeting
point of the explosive waves from two stimuli
taneous fired safety cartridges, proving that the
air was so heated by compression as to become
luminous.
In the Kammatograph, nearly 800 pictures
are taken on a plate IL inches in diameter, the
turning of handle causing slow rotary and
lateral motion, with the necessary stop for ex-
posure at every fourteenth second. The pic
lures, thus impressed in a spiral, combine in an
"animated photograph" when positive plate
ia pressed through the camera in front of a
lantern.