Amador ledger., 1910-08-26

Lamp.
A self-heating crust resting on
solid nucleus is the conception of the
earth that Prof. E. H. l.. Schwarz, a
South African geologist, finds to
agree with modern evidence. The
nebular hypothesis of Kant and Lap
lace has proven untenable, and the
new planetesimal hypothesis of Prof.
T. G. Chamberlin, the American geolo-
gist, conforms much more closely to
observed facts. This theory assumes
that small solid nucleus has been
gradually enlarged by the fall of
meteorites. When the globe was
small, radiation must have been rapid
enough to keep the mass at about the
cold of outer space, and not until the
atmosphere and water appeared could
mechanical and chemical action have
produced heat more rapidly than 1t
passed away. The physical condition
of the earth's interior is now known
from the vibrations that pass through
it. The earthquake waves recorded by
instruments are of two kinds-the or
binary kind passing through solid,
liquid or gas, while the transverse
waves cannot be transmitted by liquid
or gas, but travel in a straight line
through the earth. These waves are
suddenly accelerated when they des-
cend below 80 miles. indicating a
nucleus twice as dense as steel. The
earth's heat increases downward to a
limited depth. chemical action probab
ly does not go below miles, and heat
ing from radlum and other causes pro-
badly ceases at about the limit of
water percolation-perhaps depth of
80 miles. The lava of volcanoes is due
to local causes-not reaching below 10
or IL miles.
Molybdenum or its oxide is now com
bined with material OF great electric
conductivity to form an improved arc
lamp electrode. With an electrode of
10 per cent of metallic molybdenum
and of metallic iron, white arc of
great volume and brilliancy is pro-
duced.
The new general map of the moor
on which Goodacre has been at work 7
years is based on determinations of
1888 points, and is much more exact
than Schmidt's map.
Flies in dwellings have acquired i'll
repute as carriers of disease, though
little is known of the extent of the
harm they do. DR.. Robertson, health
officer of Birmingham, Eng, reports
that the local investigation has in
Dictated a close connection between
flies and epidemic summer diarrhoea,
and 1t is supposed that the flies spread
infection by means of germs taken
up from the decomposing garbage and
other filth on which they live. The
flies of towns are of several kinds.
Of those actually caught in Birming-
ham for naturalization, the common
house-fy numbered 1850 specimens,
or 81 per cent of the whole; lesser
house-fy l, 154, or At per cent; blue
bottle fly, $40, or "a per cent; special
fly, 100; greenbottle fly, II; bright
blue fly, 8; stomoxys calcitrans fly 3;
others, 5-the total of the five last
named varieties equaling 0.9 per cent.
The eggs of the common house fly
chiefly deposited in horse manure and
house refuse-were found to hatch in
8 to "a hours after being laid 1t was
shown that food attracted flies, and
that a greater number entered houses
on a wet day following a warm period,
evidently seeking protection from rain.
Search for new gas that shall be
very light and very cheap has been
stimulated in Germany by the progress
made with airships. Hrydogen, the
lightest of all gases, is very expensive
and, the much cheaper coal gas is com
paratively heavy. An intermediate
product is now claimed to give great
promise. 1t results from passing coal
gas through a long tube kept very hot
the separation of carbon from the by
drocarbons raising the percentage of
hydrogen, to 80, while the character
istic odor is destroyed, and the ben
zine-so damaging to balloon varnish-
is removed. The treated gas shows
great improvement in buoyancy. The
specific gravity is reduced from 0.44
to 0. 225 and a balloon of 1000 cubic
feet is given the lifting power of a
balloon of 10000 cubic feet filled with
ordinary coal gas.
The soil surveys of the United States