The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1904-12-03

SCIENTIFIC MISCELLANY.
Progress In Arc-Lighting-A British Call
to Science-An Interesting Mammal
Generating Alloy-Lightning Holes
Laboratory Gems-New Galvanizing-
Earth Wabbling by Earthquakes.
The new arc-lamp Of Andre Blondel, the
French engineer, claims three substantial i'm
provements, viz. One Of the carbons contains
certain salts that increase the luminosity the
positive carbon in the direct-current lamps is
placed at the bottom and a reflector encircles
the upper carbon The efficiency is much in
creased by these features. The light can be
varied considerably and made much whittier than
the ordinary arc. and the light is very brilliant
and economical, comparison with different
type Of apc-lamps having shown six times the
candle-power from an expenditure Of q third as
much current. The improved arc seems to
mark an advance Of much importance.
~
The deterioration Of British wheat calls for
scientific remedy. The area cultivated in the
British Isles is stated by Mr.. A. d. Hall to have
fallen from 100000 acres in 1875 to 100000 in
1908, and foreign wheats now command much
higher prices and make larger loaves, the home
wheat having become materially poorer than it
was twenty years ago. Mr.. Hall calls for ef-
forts ct improvement. He sees no hope except
in the Decentralization of good British and
american and colonial wheat, and the selection
Of grain containing strength, cropping powers
and good straw. Another writer suggests that
practical results are more likely to follow deep
cultivation.
A remarkable paca-lfke rodent described by
Dat fes rad -
mys branicki, has been known by single speci-
men found near house in Lima, and this lone
animal has represented not only species but a
genus and even family by itself. Other speci-
mems are now reported to be living in Para
museum.
The influence of the depth of the sea on the
speed of ships has been tested by the German
Navy in the Baltic, torpedoboats being used for
the experiment, and the results are curious and
interesting. At twelve knots no influence was
shown. At fifteen to twenty-one knots shall
low water acted as a serious check: but while
In four fath0ms of water the horse power need
ed TO maintain twenty knots was double that re-
quired for the same speed in ten fathoms or
more, the worst results at twenty-five to twen-
ty-six knots were obtained in ten to twelve
fathoms and the shoals Of four fathoms gave the
least resistance.
~
A remarkable property of aluminium and tin
alloys has been described by Hector Pechaux to
the Paris Academy. When freshly-flled sur
faces Of four different mixtures of these two
metals were plunged into cold distilled water,
bubbles Of oxygen and hydrogen were given OF
for two or three minutes. but neither of the
metals nor an untitled surface Of the alloys gave
any such effect. It is supposed that tempering
in casting separated the two metals into juxta-
posed molecules, which formed a thermo-elec-
trio couple and generated an electric current
until cooled to the temperature of the water.
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During an early morning thunderstorm in
April, tireball descended at Earl's Fee, in rs
sex, England, with binding fash and terrific
explosion. After dawn, three distinct sets of
holes. ranging from inches down to ] inch.
were found in the stiff yellow clay Of an oat-
field, these holes being perfectly circular, as
clean cut as though bored with an auger, and
tapering downward to the rounded bottoms.
ass
convenient pyrometer is said to be series
Of alloys of silver, lead and copper. A compo-
sition Of parts of lead and of silver melts at
1907 O.; Of lead and l Of silver, at 500 9 of
lead and Of silver, at 6OO0 and Of silver and
OF copper, at eoUo.
ars
The artificial ruby seems destined to become
commercial success if the artificial diamond
does not. By the process of N. Verneuil, the
French chemist, the ruby is produced by melt
ng mixture of alumina and oxide Of chrome
at a constant temperature Of several thousand
degrees, and in layers superposed from the out
side to the inside, in order to prevent cracks in
the mas Tho owfr
ture necessary is obtained from vertical oxy-
hydrogen blowpipe with downward directed
fame, and the hardness of the stone is secured
by an energetic tempering through sudden sus-
pending the action Of the blowpipe. The pro-
duct has admirable fuorescence, on account of
its great purity. It has all the physical proper
ties of the natural ruby, and can be cut and
given very beautiful polish. One artificial
ruby already made is valued at $500.
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Zinc is the most effective coating for protect
ing iron and STEEL and this is usually applied by
dipping the shaped metal in molten zinc, but
electro zincing or cold gaivanizing Is used for
special classes of work. A new process Is
known as ''sherardizing." 1t consists in freez-
ing the iron from scale and oxide by any method,
and then placing it in closed iron receptacle
charged with zinc dust and heating to 5OOo or
600' F. for few bours. The heat is ZOO below
the melting point Of zinc. The iron becomes
coated with fine homogeneous covering of
zinc, and the low temperature necessary makes
the process cheap while the iron is deteriorated
less than by hot dipping.
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The small irregular displacement of the earths
poles has been attributed by Prof. John Milne
to earthquakes, and now it seems that measure
ments by the Meteorological Institute at Rome
give striking confirmation of the theory. The
great earthquakes register movements-such as
the sinking of a sea bed or rising of a CONT
nent-that must change the distribution Of the
earth's mass and the position Of its axis.