The San Juan islander. [volume] (Friday Harbor, Wash.) 1898-1914, 1903-10-08
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is the greatest project now being con-
sidered by Italian engineers. Inc
Sale flows into the Mediterranean near
Salermo. but it is to be tapped In the
hills. and the water taken across TO
the Adriatic watershed to irrigate the
province of Puglia.
For measuring feeble Nominations,
like the Zodiacal Light and Gegen-
schein, Nj. Touchet has devised spe-
cial instrument, resembling theodo-
lite in appearance. 1t is provided with
n constant flame and a slit regulated
in width by a screw with divided head,
and when the illumination of the field
through the slit exactly equals the
light to be measured. a reading Is OBJ
tanned that is easily reduced to
standard.
Although there is a certain area OF
about three and a half acres on Man
haitian Island where the density or
population Is at the rate of 63O,OOo 70
the square mile, yet the city OF Paris
shows far greater average density
of population than New York. the
figures for Paris being 79,3O0 per
square mile and for New York City
proper 10000 per square mile. The
average density of London's popula-
ton is 81 1000 per square mile, and that
of Berlin 67,6OO.
The Finsen lamps are now credited
with ten cures of cancer Of the skin
out of twenty-five cases treated, and
with cures OF obstinate acne and OF
badness due to bacteria. Erysipelas
and minor eruptions have been treated
with good results. At the Finsen In
stitute are rooms for exposing patients
to electric-light baths and to sun-baths,
and an exhaustive and promising In
vestigation OF the influence of light In
various nervous diseases and In in
sanity is in progress.
/ A New York man has invented
mirror that can be made translucent
at WILL so that when placed in show
window it at first reflects the faces
Of people looking in, but suddenly turns
transparent, whereupOn the spectators
see the contents Of the window In place
of their own reflections. This Is effect
ed by means of thin film on the back
Of the glass, which, when the back
ground is dark, reflects the light from
in front like mirror, but when the
background Is Illuminated, becomes as
invisible as a pane Of clear glass.
nro 80 hn xxyint cdO IF
ersburg is a system Of electric tram
ways ON the Ice In the Neva. One
runs from the left shore of the river
to the island of Petrowsky, and an
other from the English quay, opposite
the Senate House, to the island Of
Basilio, near the Academy Of Fine
Arts. Wooden posts solidly embedded
in the ice support the trolley wires.
Besides these tramways many wooden
roads, intended for pedestrians, cross the
water In various directions. In sum-
mer bridges Of boats take the place
of the roads on the ice.
The smelling of steel by electricity
Is still an attractive problem. The
two furnaces built in Sweden in 1000
reached technical solution by pro-
ducing steel Of fine quality, but the
furnaces were ruined by fire before
commercial success had been attained.
Another furnace planned by the same
makers is to hold 1910 pounds, with
a yearly capacity Of 1900 tons, and is
to receive the current of a three hun
dred horsepower dynamo. Though
microscopically Identical with crucible
steel, the electric product is ella lined TO
excel in strength, density, uniformity.
toughness and ease of working when
cold.