Amador ledger., 1910-11-18

Fire-proof Box-Dazzling Lights
Harmful-Typhoid and Floods-Tun.
mel Wall-Laid by Increasing
Interest in Astronomy-Piers Sunk
by Pile -Driver-Long- Dormant Mem
ory-Stage Daylight.
The "Lumeter" is an instrument
designed by J. S. Dow and V. H.
Mackinney, British opticians, to
measure the surface brightness of H.
Illuminated objects, and it gives a
simple means of studying the distribu-
tion of lighting. The illuminated OBJ
ject under test is viewed through an
aperture in an illuminated screen,
which is kept at uniform brightness by
suitably placed small glow lamp.
The relative bril1iancy of the observed
surface and the screen can be adjusted
until they appear equal, and a gradu-
ated scale then indicates the surface
brightness of the object under test as
compared with the stanc ard illuminated
screen Trials of the instrument in
clas-rooms, work-rooms, etc., have
shown surprising variations in the
lighting of interiors. In a technical
college classroom, 25 by 80 feet in
size, with large windows on the
street side, the illumination of the
best lighted desk at S O'Clock on a
September day was ~ foot-candles,
while that of the poorest seat was only
0.6 foot-candle, and the illumination of
the blackboard varied from 5-foot-
candles at one end to o.. at the other.
In one of London's underground tubes,
the horizontal illumination was IL to
1.3 foot candles with the train at rest,
falling to or to 90 foot-candle on
entering the tunnel.
A new French case for protecting
jewels and important papers
from fire consists of two asbestos
boxes of different size, one being
placed within the other and prevented
from touching by number of asbestos
blocks. The poorly conducting ashes
tos and the insulating air space com
bine to keep the inner box quite cool
while the outer one is strongly
heated.
The glare of artificial lights has been
found by Prof. Gariel, of Paris, to be
far more injurious to the eyes than
their ultraviolet rays. He urges that
the shades used should not only cut
out the ultraviolet rays, but should
diffuse the light SO that it will show
no dazzling spots to the eye.
Typhoid fever and other epldemics
prove to be diminished by floods, in
stead of being increased, as has been
The former conclusion has
been reached by Jacques BertiIlon, a
French investigator, after a study of
the effects of the great 1910 inundation
Of Paris and of serious floods in a
number of other European cities.
Aside from the cleansing action of the
water, however, it is probable that
after disasters health officers give
more thorough attention than ordl.
narlly to disinfection and to isoIating
cases of disease. Comparing the
Hooded sections of Paris with those not
reached by water, it was found that
typhoid fever was rather more pre-
vaIent in the latter; and in 81 flooded
areas there were "A deaths in 13
weeks before the flooding and only "a
in the same number of weeks follow
ing In 10 floods in Dresden and 6 in
Vienna no increaes of typhoid resulted.
Encasing a tunnel lining with grout-
ing from flexible hose has been sue
tried on Swiss railway. A
mixture of 162 pounds of Portland
cement to 9 gallons of water was used
in cylindrical vessel holding about 80
gallons, the cement being kept stirred
by hand. revolved paddle, and COM
pressed air at about 78 pounds per
square inch was admitted to the cylln-
der through pipe entering the top.
The lining being perforated with to 8
holes, the water back of it was forced
out by a strong blast of air. The
cement mixture was then forced
through the hose into these holes by
the air pressure in the cylinder. and on
hardening made the lining quite water.
tight.
The astronomical observatories are
found by British astronomer to have
increased from 60 officially recognized
in 1859 to 230 at the present time. Of
those now existinp the ITnitad Statas