Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1891-04-12
Every Day Science,

A HANDY combination lock- now used upon
tricycles boats, chests and boxes, is fitted with
numbered dial. very much like those used for
safes and vaults.
PAPER racing boats have been in successful
use for many years, but ships boats Of rh1s
material have never been used. The Navy
Department has decided to place a paper
whaleboat gig on the next vessel fitted out with
boats from the New York navy yard.
A GERMAN chemist claims to have discovered
a preparation, which, applied to the soIes Of
boots and shoes, increases their wearing quail
ties from 500 to 200 per cent. The soles are
supposed to become more flexible by the pro-
cess, and poorly tanned leather after being SUBJ
jected TO it is said to become good as the best
leather made. The sole treated with this pre-.
paration becomes waterproof
A NEW style of illustrating machinery has
been attempted with considerable success, b
which, on a single picture, two sides of the
machine clearly shown. This effect Is OBJ.
tanned by placing mirror in such a position
that when the picture Of the machine and
mirror is taken, that portion Of the machins
reflected in the mirror is also shown in the
picture, and from this photograph an engrav>
ing is made.
FREE lectures are now being delivered In
various parts of the country to those who wish
to take advantage Of the facility with which
languages can now be studied by means Of
phonograph cylinders. Sets of cylinders are
also provided which contain the conversational
course OF a well-known system In French, Ger
man, Spanish or Italian, and with each set Of
cylinders set of books is furnished, so thas
the eye and ear can be educated az the same
time.
A NEW bicycle treadle increases the leverage
on the crank arms on the downward stroke.
The operator is also, by this arrangement,
enabled to press downward with greater force
upon the forward outer foot rest the leverage
being increased by the distance from the crank
spindle to the outer foot-rest bar. By this inn
provement, the rider can more easily overcome
dead center, and, should the pedal be acct-
dentally dropped, its increased length factlt-
tates its recovery.
IT ia very satisfactory to know that notwiths
standing the progress of the electric light, the
consumption of gas is increasing, and the older
illuminant Is likely to play in heating a mora
important part than it has ever occupied in
lighting. The lowering of the price of gas in
Brussels has afforded striking illustration of
this. There has been marked increase in
that city of the use of gas for heating purposes
of all kinds, and the gas authorities have de~
termined to charge certain price for the
rent of stoves, and for. other special applica4
tions.
THE principle of expansion and contraction
of metallic loop made of German silver and
steel, when exposed to varying temperatures.
has been utilized for automatically shutting of
gas when il has been blown out, instead OF be-
ing turned OF in the usual way. One end of
the loop. which is adjusted close to the gas
fame is free, while the other is secured to the
fixture. A valve controlling the gas is attached
to the free end, and when the gas is burning ths
valve is open and the gas freely escapes. II.
however, the gas is blown out, the loop will
quickly cool and contract, and the valve viii
shut off the gas.
AN ingenious method of utilizing gravity ins
descending grades has been worked out by an
italian engineer. The engine IN running down
a grade congresses air, which is utilized in
propelllng the train up part of the next sue
ceeding ascending grade. The accnmulatorss
are constructed for pressure OF loo pounds
and the mechanism designed for the alternate
compression and utilization of the air cons
prises three cylinders, two Of which are OF
equal diameter and the third Of smaller size-
These three cylinders are connected to one OF
the two coupled axles carrying the load by
means of the usual cross-heads and connecting
rods. When ascending grade these cylinders
work as a compound motor. and during rha
descent the action is reversed and they oom-
press the air into the accumulators according
TO . regulated pressure.