Amador ledger., 1907-02-22

NOW EHOlOmeCer.-Gn Inc AuCOmODile
az a Street Dlsinfectur. "A Novel
Danger on the Rhine Gro wing
Alumina. Caterpillar Professions
A Sea Going Machine Shop
Milk Stone. = Unexplained Ell ects
of X Rays.
FoI testing the power of lamps a
Mayence optician has devised a novel
photometer based upon the varying
electrical resistance of selenIum under
different illumination. The apparatus
includes two mirrors lighted respect
lively by a standard lamp and the
mn to be tested, while seIenium
cell rapidly osciIIating between two
given positions is alternately lighted
by either. The electric oscillations
set up are shown by an ammeter. One
lamp is moved until these oscillations
cease and the respective distances
from the photometer will then give,
according TO a we'll known rule, the
light intensity of the lamp under test
as compared with that of the standard
lamp.
The automobile has been condemn
ed TOR the surgeon for two reasons
that, il he dives the machine him
self, it causes trembling OF the hands,
and that the apparatus must con-
taminaIe the hands with the germs of
street dust. DR.. Fieux, of Bordeaux,
dismisses both OF these indictments.
The embling of the bands occurs
only in men of such high-strung
nervous temperament as to be untitled
for operating at all, and tests of the
dust under the hood of an automobile
showed no micro-organlsms of any
kind. The heat of the motor actually
destroys the microbes in the dust
clouds, so that, instead of scattering
disease the machine really disinfects
the road.
A recent Investigation shows that
the deaths of two children on a Rhine
boat we're due to the cargo of ferro-
silicon. For two or three days the
children occupied cabin directly
over the hold where the keys of iron
we're placed and they were poisoned
by phosphuretted hydrogen evolved
from some impurity probably
calcium phosphide. Within the last
six months several other sudden
deaths have occurred on Rhine boats
carrying ferro- silicon.
A curious phenomenon, which he
calls growing alumina,'' is descriu-
ed by L. a. Vaughton a British ex-
perimenter. a drawn-out capillary
tube contains globule of mercury
and Is placed vertically a fraction of
an inch above an aluminium plate.
The mercury and the aluminium act
respectively as anode and cathode
between which electric sparks are
passed. AS the sparks pass, cIr-
cular crater of neary pure aIumina in
the form of a teathery moss is de-
posted around the spot aud grows TO
considerable size. 1T the deposit is
removed another forms without the
passage of further current No
growth occurs in an atmosphere of
hydrogen, and very little in oxygen.
The alumina produced has the re-
markabIe property of acting on a
Photographic plate even~ through
celluleid. Asuggesi cd explanation is
that the sparkling forms an amaIgam
through the spraying of mercury on
the plate, aud this is decomposed by
atmospheric moisture, depositing
the aIumina and setting free the
mercury, which is ready to repeat
the process. The photographic action
is that often observed when hydrogen
peroxide is produced.
Certain moth Iavae living in pines
in parts of France have been seen
marching in single file, the leader
spinning thread to which each
! follower adds, and one of these
singular professions noticed last
April near Arachon included ia
individuals. Ihe professions are
formed at night as the larvae leave
their nests to feed on young leaves
and in the day when they descend to
burrow IN the sand and pass to the
pupa stage.
The new floating dockyard of the
British Admiralty is a special vessel
suggested by a trial of an obsolete
cruiser as a temporary repair ship.
The new vessel of i, 600 tons, Is 450
feet long 55 feet. beam, and 40 feet
deep, and carries a crew of 300 skill
ed artisans The fittings include