The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1900-02-24
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.

Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
iron Smelling by Electric Arc-Cheap
Lamp Oil-Tunnel-Lighting When Need
ed-A Useful Material-The Black OF
Diamonds-An Improved Artificial silk
Birds Colored by Light-The Dust we
Breathe-Matches Without phosphorus.
Iron and steel are produced in the Stassano
process by smelling the oxides Of iron in the
heat of the electric arc. The furnace is formed
ny purr1ng tOKrtner the uases OF TWO truncateu
cones, third similar cone serving as the cru
chile. Within the furnace. somewhat above the
opening of the crucible. are two cylindrical car
bon electrodes inches in diameter and yard
long. The ores are oxides or carbonates, the
latter requiring preliminary calcination, and
these are pulverzed, freed from gangue, an
alyzed to determine the exact proportion of
carbon, lime and silica necessary for reduction,
and compressed into blocks with the aid of q
small percentage of tar. These blocks, broken
up, are used to charge the furnace. The cost of
these preliminary operations is greater than
usual, but the energy required for one ton of
metal is only 5000 horse power hours, which is
said to correspond to saving in fuel of nearly
one-half. Alloys are produced by adding other
ores in the necessary proportion.
Apollo Illuminating oil, yielding an odorless
and smokeless fame without glass chimney
and with small consumption of oil, is stated by
German authority to be thus produced: Fusel
oil, cheap by-product of alcohol distillation, is
mixed with Is per cent. of milk of lime, which
decolorizes and purifes it, and then with rs per
cent. of petroleum. On standing "a hours, the
lime separates in scales, when the oil is poured
Off.
Incandescent lamps, a meter apart and at the
heightof the car windows, are to be placed along
the side of the Batignolles tunnel. near Paris.
These will be automatically lighted and ex-
tinguished by the passage of the traid. giving
passengers sufficient light, and requiring much
less electric energy than If lighted continuously
."A
At recent meetlngof engineers, it was point
ed out that paint does not prevent overhead
bridges from being destroyed by locomotive
gases in few years, but that wood ceilings pro-
tect the steel.
One of the most valuable of recent insulating
materials appears to be that known as ambroine
This is mixture of amber and other fossil
resins with asbestos, mica and other silicates
the substances being pulverized and made to
combine by standing and chemical treatment, |
and finally placed In moulds and subjected |
simultaneously to great heat and pressure |
One important advantage of the material is that |
it does not shrink in the moulds SO that inter- |
changeable pieces are readily made. Ambroine |
is claimed to be an insulator of the highest |
order, sheet 1-75 of an inch thick resisting |
5000 volts; it absorbs moisture even less than |
hard rubber; it is much stronger than ebonite, |
and 1t wfthstands heat and shock, and is unaf- |
1ected by the air. 1t is absolutely HOMOGENEOUS |
and takes high polish. The cost of the moulds |
restricts its use to articles needed in consider
S''sanceu injuries OF railway lines.
OF the various enclosures in the transparent
diamonds Of Brazil and Cape Colony, the most
numerous are black, affording, when abundant
the variety of crystallized carbon known as
''black diamond" A late investigation by NJ
Henri Moissan shows that these black enclosed
matters consist of different form of carbon. A
black diamond was finely pulverized. and the re-
~sulting blacklist gray dust was heated half an
hour in current of oxygen having tempera-
ture 200 lower than that of combustion of the
diamond. There was slight escape of carbouic
acid, the diamond dust becoming white It is
evident therefore that the coloring matter burns
in oxygen, yielding carbonic acid and that the
carbon burned differs from that of the colorless
diamond.
Much is being expected from viscose, the
product of the reaction between alkali-cellulose
and carbon bisulphide discovered by Cross and
Devan. 1t proves to be possible to spin the ma
terial, silky cellulose thread being easily OBJ
tanned. The cost is but fraction of that of
Chardonnet silk, while it is claimed to have the
advantages of being non-explosve and quite
unaffected by water and alkali.
80
Colors ground in oil and thinned with petro-
1.r,r4
oil-have been found by French artist to have
many advantages.
study of the birds of Ceebes has convinced |
Messrs. Meyer and Wiggesworth that light OPP
crates to change the color of birds much as it |
affects colors in lifeless matter. Where the
wing rests on the body, there is almost always a
differences very marked-in the coloring
of the shaded and the exposed parts of the same |
feathers. The difference is sometimes that of |
white and black: and in one species of paroquet
the wing-feathers are blue-green next the body
and black on the other side. In other instances |
of change observed, the tail-f feathers were paler
in parts protected from light. But while some |
open air birds are black when seen from above |
and white from below, the opposite effect may
often appear in Gagged birds. the plumage becom- |
ing dark in the shade and more brightly colored |
when exposed to light.
"a
British investigator has found that in a SUI
burban locality the dust particles number 10000
per cubic centimeter in the open air and 1900 |
in quiet room; while in the city the totals |
were 100000 when taken from roof, 100000 in a |
court, and about 100000 in room. Yet, though |
the dust is the great carrier of micro-organisms,
the danger from the germs inhaled seems to
have been exaggerated. 1t is proven that there |
is but one miorobe to each 100000 dust atoms,
and it is calculated that in seventy years of life
in the metropolis man would absorb from the
air only some 75,COO,OOO microbes, or about the
number he drinks in half pint of unboiled
milk.
~
A revolution in match making is suggested by |
Giovanni Graveri of Buenos Ayres, who claims
that phosphorus may be replaced by harmless
perthiocyanic acid. This is a compound of two
atoms each of hydrogen, carbon and nitrogen,
with three of sulphur. 1t can be made from
the by-products of several processes, such as |
the publication of coal gas or the Leblanc soda
manufacture, and it is said to be already cheaper
than phosphorus
sFs
A cobra measuring somewhat over X feet,
taken at Jaffna, Ceylon, is stated to be by far |
the largest ever recorded