The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1902-12-06
Correspondence Baltimore County Union
SCIENTIFIC MISCELLANY.

Correspondence Baltimore County Union
SCIENTIFIC MIS- CELLANY.
Near Absolute zero-Insomonia Treat
ment In Java-Cheap Hydrogen-hy-
draulic Blasting-A Land of Museums
The Region Of Shrubs--Cause OF
Sleep.
Liquid hydrogen, first obtained by James De-
war in 1898, is by far the lightest liquid KNOWN
it's density being. only one-fourteenth that Oh
water, and piece of pith wood is the only SOHO
light enough to float on its surface. 1t is by lar
the coolest liquid, its boiling point at atmos-
pheric pressure being minus 252.5' q. Unoer
the air-pump it cools to minus 25S0, when 1t so
lidifies as frozen foam, and this on further re-
duction of pressure is lowered in temperature
to minus 26OO, or only 13o above absolute zero,
this being the lowest steady temperature yet
reached. The solid may be had also as clear
transparent ice. only one-eleventh as heavy
as water. Under this cold every substance
definitely known except helium solidifes. and
LIQUID hydrogen may be said to introduce us
to a world of solid bodies. The liquefactIon OF
helium, the difficult and costly problem upon
which Prof Dewar is now working, is expected
to yield temperatures within to 10 degrees OF
absolute zero. 1t is anticipated that liquid
helium, though twice as dense, will have but
fourth of the refractivity of liquid hydrogen,
the least retroactive liquid now known, and it
will be nearly invisible.
~
Sleep is produced by the Javanese, states
French author by COMPRISING the carotids
These large arteries, which carry blood to the
BRAIN run upward below the ear from the lower
front of the neck, and are pressed with hand
on each side of the neck. The brain congestion
producing wakefulness is thus reduced.
81
BY the new process of n. George Claude, by
drogen is extraced from illuminating gas by
passing the latter through a tube plunged in
liquid air. The hydrocarbons are almost in
stantly liquefed, and only hydrogen escapes
from the tube.
! The hydraulic mining cartridge of James
Tonge, Jr is designed to replace explosives in
mines liable to contain fredamp. 1t consists of
a steel cylinder twenty inches long by three
inches in diameter. across which are arranged a
series of eight.small telescope rams, and in use
the cartridge is pushed up into drill hole in
the coal and hand-pumps force water into the
cylinder, driving out the rams. A pressure Of
three tons per square inch can be readily 90
tanned. In about ten minutes the rams bring
down the coal in large pieces, and with much
less waste and fragments than when explosives
are used A test of two years has shown the
! cost to be about the same as ordinary mining
But the coal is more valuable, and the dangers
are greatly lessened, many deaths resulting
yearly both from accidents with the explosives
and from the igniting Of explosive gases. The
British Society of Arts has found the cartridge
worthy of an important prize.
"a
The deporting to Siberia of so many of Rus
sia's scientific men has brought about curious
condition. Buried in this land of isolation, these
trained minds have devoted themselves to stud
les of their narrow world and Prof. G. F. Wright
notes as one result that scarcely town of COCO
inhabitants is without public museum under
a competent curator, one of the finest collec-
tions being at unheard of Khabarovsk. The
museum at Irkutsk is nearly century old that
at Minusinsk is visited by students from all
lands.
In an inquiry by the Society for Psychical Re-
search, "a 900 have denied ever having had hallu-
cinations, while 5000 haye reported false i'm
pressions of seeing or being touched. Mr.. +.
Legge finds that in the larger part of the latter
cases the persons supposed they saw living or
dead acquaintance. He concludes that uncon-
scious memory plays the greatest part in these
receptions, and that visual records of the brain
are more often excited than those of hearing
and touch because more numerous and varied.
80
French industries now use more than 5OO,COC
horsepower from waterfalls, about twentieth
of the total available.
81
Wireless signals meet with numerous obsta-
Giles. Experimenting with signals between YES.
sells, Capt. H. b. Jackson has found that the
waves were abruptly cut off when the ship car
rying the receiver passed behind a promontory
of iron-c charged rock 800 feet high, but were
less affected by limestone, while the signaling
distance was reduced still lessor about one
half-by cliff of porous coral sandstone 25t
feet high and six miles across. Bad weather and
moist, dust-laden winds caused the waves to be
absorbed to great degree. Flashes of light
ming always produce signals, which are usually
something like the letters lei" in the Morse
code. Absence of earth connection for the re-
ceiver reduced the signaling distance so or ever
20 per cent. and when the transmitter lacked
earthing the signaling distance was lessened
per cent The air wire proved indispensable, nc
signal being sent more than two miles without it
~
A list of Wyoming trees published two OF
three years ago named 81 species, and late list
of the shrubs of the State embraces 105 species
About dozen species-marking the border line
are given in both lists. Of the shrubs, there
are thirteen species of willows, nine of currants
and gooseberries five roses, five sage-brushes
and ten RIGHTEOUSNESS. The predominance OF
shrubs, points out Prof. G. E. Bessey, is nota-
BILE feature of the woody vegetation of the
highlands of the West.
~
That the phenomena of sleep are due to car
bonic acid in the body is the theory of DR.
Raphael Dubois. An excess of carbonic acid is
produced during waking hours by oxidation OF
food, etc., and the an@sthetic effect of the gas
seems to regulate waste by bringing rest be-
fore we have drawn too much on ourreserve re-
sources. DIR. Dubois justifies his conclusion by
pointing out that an excess of carbonic acid in
the air brings sleepiness and fatigue even while
reducing oxidation or the body's work.
&**
The flavor of milk is thought by a Koenigs-
burg exterimenter to be due less to vegetables
eaten than to pecuiarities of the animal.
Personally Conducted Tours via Pennsyl-