The workingman's advocate. [volume] (Chicago [Ill.]) 1864-1877, 1871-06-03
SCIENTIFIC AND MECHANICAL.

IL is well known that icebergs cool the
water around them to very considerable
distance. An American gentleman, nam
ed Dion, has made this fact the foundation
Of an invention TO protect vessels against
collision with iCebergs. He proposes 70
place on the bottom of STEAMERS or other
vessels an apparatus SO arranged as to
sound an alarm on the instant the ship's
keel enters stratum of cold water. The
invention is said TO have been suggested bv
the supposed fate of the lost steamer City
Of Boston.
GrLrER's GLUE.-A very superior ar
tic!e Of the so-called gilders' glue is obtain.
ed BY cutting rabbit-skins into fine shreds,
and boiling in water, then turning the mix
ture into basket, through which the liq-
uld passes, leaving the refuse behind.
About fifteen hundred grains of sulphate of
zinc and three hundred and seveuty.6ye Of
alum are then to be separately dissolved in
pure boiling water, and poured into the
first mentioned liquid, and the whole we'll
stirred together while hot. The mixture
is then to be passed through seive into a
rectangular box, in which the Jelly remains
twenty-four hours in winter, or about forty
eight in summer TIE mass now having
become solid, is to be separated from the
box, and cut into slices Of proper Ithiok-
ness, and laid upon nets to dry, either i'm
the open air or by means Of some kind Of
artificial heat. .-Erchdnge.
THE CHROSoPHER-"Gr Greenwich Tine
is kept all over England and Scotland by
all the railway, postofhee, church, and
watchmakers' clocks. The time is sent
daily, at 10 o'clock, from Greenwich OBJ
servatory, all traffic over telegraph wires
used for the purpose being suspended at
9:58. Sixteen Of the most important cities
are in direct communication with G1 een-
wich, and places through which the wires
pass are aware Of the completion Of the
circuit which announces 10 o'clock. The
principal London watch and chronometer
makers, such as Dent, Vulliamy, Barraud,
Walker, Frodsham, and others, are COM
munioattd with even more frequently.
Guns are fired at the ports of New Castle
and Shields at | O'Clock daily BY the same
means. The clock at Greenwich, which
automatically sends the time, is called a
chrOnOpher, and il corrected to variation
Of twentieth part Of second in a week.
This is a useful arrangement in Eng
| land, where the country is so small that
one uniform time can be kept without vary
| ing more than few minutes from solar
tune, even in the most distant cities But
Il could not be practiced in the United
States No assimilation over a part Of the
country would do anything but confuse and
perpler the public and if the clocks Of
San Francisco kept New York time, they
would vary from the solar time by differ
ence Of more than three hours
The invention of a new microscope
cal writing machine, il England, claims
that the entire contents Of the Bible can,
with the help Of his contrivance, be written
twenty-five times in the space Of a square
inch
THERE have been found in the eayerns
" Acquitaine, France, some very cur. Jus
engravings Of the pre- historic period, one
Of the most remarkable Of which Is an en-.
craving on q reindeer's norm, representing
q male bison pursued BY naked man, who
s grasping the animal by the tail with one
hand, and with the other plunging lance
lhto its body. The absence Of clothing is
believed to prove that the ''man Of the Pc
Rod" then was accustomed to wear none
CHICAGO consumed in one week 1,044
head Of cattle, 1851 hogs, 3,309 sheep
and l6l calves,