The Penn's Grove record., 1883-04-21
The Field of Science.

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The total population Of the United
States is, in round numbers, $4,000, 900.
Of which 43,476, 600 are native born,
and 6,6s0.000 are foreign born. The
colored people number 6,632, $40. Thus
about every seventh person nearly is a
negro, and every seventh person nearly
foreign born.
The black magnetic sand that is
found in abundance in the washings of
our gold mines is, by "a new process,
utilized in the manufacture of cast
steel direct from the sand. Eight
pounds of sand yield five pounds of steel.
The Stag that is left is valuable as
cement for fire-proof roofing.
A liking for one-story factories has
been developed among the manufact-
urers of New England, and they are
being built in many cases where the
nature of sites permits. They are said
to be economical, handy, safe and free
from that vibration which looms i'm
part to tall structures.
According to the Pacific Medical and
Surgical Journal, the death rate in San
Francisco for the year ending June,
1882, was 21.34 Even this rate, low
as it is for a large city, is higher than it
has been for ten years. The whole
number of deaths is given at 500S, of
which 527 were among the Cinnamon.
The Lancet condemns the new article
of female attire called the "crinoiette. "
1t is an impeachment to walking, Induces
an uneven bodily temperature, adds
another to the many burdens borne by
the waist, and bids fair to compete
with crinoline in encouraging a preva-
lence of deaths by fire.
Exposure to light and air will destroy
ebOnite. Strange to say, merchants
and others appear to neglect this fact,
and no doubt experience considerable
loss. Caoutchoue tubing ought, when
not in use, to be kept in a dark place and
in water, to which Il little ammonia
may be added if the rubber begins to
show any signs of cracking.
A contemporary maintains that the
persistent use of the microscope is the
only a whereby the necessity for a
change of yeast in brewing can be as
certained, and that the examination
must be kept up from day to day. As
500 as the cells are seen to become
elongated and lose their round shape
there is something wrong.
The Scientific american says that the
haulage of our railways now employs
e 1900 locomotives, and the aGgre-
gate cost to run them, such as fuel
water, oil, repairs and engineers is
about 800, 900, 900, or not far from 5000
a year for each machine. The item Of
fuel alone is 1913, 000, 900, but the
greater portion of this fuel is practi.
cally wasted.
Steel tools sprung in hardening can
be Strengthened in tempering. Hardened
steel, when not enough to change the
color to straw color or purple, is about
as pliable as annealed steel when cold.
So pieces warped in hardening can,
while hot, be Strengthened with a ham.
mer, OF, better, with a screw-press
without danger of breaking.
Stable-keepers are among the health.
lest of men, and considered especially
free from respiratory affectiohsl al.
though much exposed to cold and da4p,
Some attribute this to the ammonia
evolved from the manure piles, and ii
S said in confederation that little breast
amulets of carbonate of ammonia, OF
spraying of the throat with diluted
liquid ammoni, gives sure relief in bron.
chial attacks.
Professor Putnam suggests in his re-
port, as Curatorof the Peabody Museum
of Archaeology, that it will not dc to
draw too large differences from the find
ing of stone implements. That our recent
Indians, he says, fused many exceed
ingly rude stone implements can not be
questioned, and even to-day, among the
Western tribes, stones picked up at ran
dom are used for various domestic pur.
poses, and when a camp is changed
many such are left; with other things
which are of too little value to be taken
away. From these facts it is evident
that the rnder implements and utilized
natural forms are not certain evidence of
the period of development. of the people
who made use Of them. That we, in
camping out, are so often forced to make
use of stones, shells, bones, and withes
of roots or bark, should be considered
in drawing deductions from the rude
character of any set of implements"