The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1906-03-17


SCIENTIFIC MISCELLANY.
The New Industrial Metal-A Botanical
Puzzle-The Strongest Material-A Pro-
Centrator-Lime for Fire. Distinguishing
The short-Wave Microscope-Glow-
Lamp Fires.
Metallic tantalum. which is Of such interest at
the present time, was first prepared by DR.. Wer-
ner Won Bolton by submitting tantalum tetrox-
idc to an alternating electric current IN vacu-
I'm tube. the metal separating at the cathode.
In later process, mixed salt of tantalhm flu
oride and potassium fiuoride is reduced by potas
stun. and the resulting mixture Of pure metal
and oxide Is separated by fractional distillation
The metal e 90 ductile that It can be drawn into
q wire 800 Of an inch in diameter. Mixed with
unaltered oxide, IL becomes harder than the dia-
mond and tougher than the best steel, and at
moderate cost It would be the ideal battleship
armor. AS lamp llament, tantalum uses only
half as much current as carbon for the same
light. A popularity of tantalum is that 1t some
times assumes the passive state, and cell of
two electrodes Of this metal. with sulphuric acid
AZ eIectrolyte. will not allow alternating cur
rent to pass. Substituting platinum for one
electrode. the current can pass in one direction
only.
The problem of the ascent Of sap in trees. an
English botanist points out is yet unsolved. It
appears that in the highest trees the total pres
sure would be nearly 100 atmospheres. and as we
cannot suppose that leaves can exert so intense
osmotic suction. the only theory at all probable
IL that the living cells exert some sort of pump
ing action in the wood.
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with tensile strength often exceeding 100000
pounds per square inch, steel piano-wire seems
TO be the strongest material known, and it pos
sesses the additional valuable property of very
high elastic limit.
The new building material known as "krem-
nite'' is made in factory near st. Petersburg,
and consists Of powdered clay. sand and huor-
spar melted together at high temperature.
The molten mass may be used like iron for
nodded castings as well as blocks. The material
can be colored in variety of shades, may be
ground or polished, takes glaze well. and gives
good imitation Of colored marble or other nat
ural stone. It may be cast in large pieces Of any
desired form. Itiswell adapted forarchitectur-
al and artistic purposes, yielding such products
Is hollow bricks, for buildings and stoves. fancy
marblelike bricks, tiles for floors and sidewalks
and even thin corrugated plates for roofs.
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a N0tCA aAACAtAEI pAOccco Sudb 10 DcAu8 8cu-
orally adopted by mining works In Germany is
designed for quickly melting any small portion
OF large mass Of metal. Such an operation is
Of great importance, for example, for opening
the cloeged tapping-holes of blast furnaces. The
point to be acted upon Is first heated by the
oxyhydrogen blowpipe or electric arc. and oxy-
gen under high pressure is thrown against it.
The enormously high temperature thus gene
rated at once liquihes the surrounding parts.
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The use of milk Of lime for quickly and effec-
lively extinguishing fires in coal mines is
recommended by Inspector Wolfgang Hummer,
e German. The suggestion is not new, but has
been newly tested with satisfactory results. The
emnIsion-which can be used with hand or power
pumps-runs into and fills the crevices Of the
coal or mineral
A peculiar process for separating non-mag-
netic particles like gold from sand has been
patented By L. T. Weiss The metallic particles
IN mass are electroplated with iron, by special
apparatus and can then be separated by any
magnetic method.
Improvement of the microscope has been the
aim of recent inventors. In the ultra micro
scope new method of illumination gives WISH
bility to particles heretofore outside of the line
OF sight; and in the still later ultraviolet
microscope the mode of illumination is a chief
feature. The second instrument uses light of
wave length Of 275. while the shortest wave
length not abeorbable by ordinary lenses is $50.
The difference depends upon the employmentof
quartz lenses. the source of light being cadmium
electrodes. and the detail obtainable with the
short rays is remarkable. The naked eye sees
nothing through such microscope. an eyepiece
containing fuorescent screen being necessary
to convert the rays and make visible picture
Of the object in green. The huorescent screen
IL only for focusing. however, ana the real re-
suits are obtained by photography, the plates
upeinE very sensitive TO the rays from the cad
MUM electrodes. The results differ much from
those of ordinary illumination. some structures
being penetrated by the cadmium rays while
others are not.
rather unexpected danger in coal mines, as
also in other places. has appeared. In an
English mine an ordinary 100-volt 16 candle
power lamp proved to be capable of causing
smoke to rise within three minutes when i'm
beddeD in coal-dust and of producing flame
within rs minutes when laid on the top of coal
dust. In other experiments, heat was generated
90 rapidly that when the lamp was partly covered
by coal dust, the bulb exploded in four minutes
o. 1902 F.. and at certain point combustion was
begun In the dust and continued after removal
of the lamp. Careless laying down of lamp
might start a fire quite unnoticed.
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A steel of special hardness, patented in \
Germany by F. Munster. results from subjecting
the molten metal to blast of nitrogen.
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