The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1898-11-20
SCIENTIFIC.

Gelatoid, a mixture of gelatine with for
maldehyde, is being used for unbeatable
goggles to protect the eyes of workmen ex-
| posed to flying particles of stone, metal or
| wood
| French violin makers report that alum
inium, when used for stringed instruments,
| produces a richer sound than wood espe-
cially with the higher notes. and the expert
mentS with the new material have been en-
Iirely successful.
Osmium threads for incandescent electric
lamps, giving a very brilliant light, have
been patented in Germany The threads are
hollow, the osmlum being coated upon
thin copper wire, which is evaporated at
high temperature.
The pure water distributed to the in
habitants of Blankenberge is that of the
Bruges canal after filtering through beds
of sand and then subjecting in sterilizers to
an electric current al pressure of 1000
volts All traces of microbes are destroyed
The electrical plant has a capacity Of about
hfty-tive horsepower, and about IS, 600 cubic
feet of water per day are treated in sum-
mer and 10000 in winter.
The later researches of Surgeon Ross of
the British army, have not only proven that
malaria can be acquired from mosquito
bite, but that the malaria parasite is mostly
one OF insects and only an occasional visitor
to man. Particular species of malaria para
sites even demand particular species of
mosquitoes-a fact at least partly explain
ing apparent vagaries in the distribution of
varieties or malaria. When ali is known
Europeans may be able to live in climates
now made deadly by this pest.
Cape Colony is almost treeless, it's forests
covering only S53,2SO acres, or little more
than quarter of 1 per cent. of the total
area of the country. Russia and Sweden
each nave AZ per cent. of their territory I'M
der forests; Germany, rs per cent: France
16 per cent, and Great Britain and Ireland
per cent. The need of Cape Colony is
Pnnnh1GiZp6 nv he hna ffor,
wood, and the conservator of forests urges
that tree plantations be formed wherever
the annual rainfall exceeds fifteen inches.
A curious experience is related by a ply
stefan of Meudon, France. To examine the
throat Of one of his children he held
lighted candle before its open mouth and
placed the handle Of spoon on the base
of the tongue. when there was a sudden
flash of blue flame from the throat and the
doctors muStache and the child's lips were
slightly burned. 1t is explained that the
spoon probably produced a slight retching,
which brought a little infiamnable gas from
the stomach.
Probably the most compact heat engine
ever attempted is that driven by carbon
dioxide. A horizontal motor Of this kind
exhibited by Mr.. w. F. Roberts to the
Franklin Institute had bedplate 24x14
inches in size and a total weight OF only
eighty-five pounds. Yet it was claimed that
the engine could develop twenty-five horse
power running at 1000 revolutions per min
ute under a pressure OF 1900 pounds per
square inch. The carbon dioxide was con-
tanned in liquefied form in steel cylinders
and was heated on its way to the engine in
a small coil Of copper pipe.
A problem for scientific men and me-
chanics has been raised by British COM
mittee on dangerous trades. The use of
beds of lead by file chtters is a frequent
cause of lead poisoning, and not less than
seventy-four cases have been reported in
one district during the last three years. A
substitute for lead as a rest for the files in
hand cutting is what is wanted. Paper has
been used in Germany for light work; clay
and fine sand incloSed in canvas, wood cop
per, vulcanite and various compounds OF
rubber and gutta percha have been tried
and discarded: and zinc and pewter are too
hard.
The new primary battery OF O'Keenan,
claimed to be a cheaper source Of electric
energy than any other primary battery yet
devised. has negative pole Of zinc. and 4
positive plate ar spougy lead. like the mega