The Indiana State sentinel. [volume] (Indianapolis) 1868-1895, 1883-05-16
CURIOUS, USEFUL AND SCIENTIFIC

Of 1862 houses inspected by the London
Sanitary Protection Society last year 6 per
cent. were found to have drains completely
choked up preventing ali communication
with sewer. In III houses the soil pipes
leaked, allowing sewer gas 20 enter the
house. Perhaps it is no better here.
Where the color on a fabric has been &C.
cidently or otherwise destroyed by acid,
ammonia is applied to neutralize the same,
after which an application of chloroform
will in nearly all cases restore the original
color. The application of ammonia is COM
mon, but that of chloroform is but little
known.
Professor Conn, of Breslau, believes that
states lead to shortsightedness, and would
substitute pen and ink, or an artificial white
slate with black pencil manufactured in
Pilsen. Black or white is proved by ex.
pertinent to stand out most clearly to the
eve. The Zurich School Board forbids
states. They are noisy, and invite dirty
habits in erasure.
Much was expected from the discovery
made by Professor Boil that the images OF
the objects remain on the retina of amin ais
that the last scene of mysterious murder
4 WOuAO Do properly the
eyes OF the victim. Actual tests have
shown that the optogram can be of no use
| in detecting crime. DIR. Ayers made more
than a thousand experiments in the labora-
tory of Professor Kuhne, at Heidelberg, and
met with poor success. The best result was
obtained by exposing the eye of living
rabbit which had been dosed with atropine
to Photographic negative, and even in this
case the ontogram was imperfect, indistinct
and evsnescent.
4 Do not empty the boiler under steam
pressure, but cool it down with the water
in it; then open the blowout tap and le:
the water pour out. To quicken the cooling
the danaper may be left open and the steam
blown of through the ssfety-valves. Dc
not, on any account, dash cold water on any
of the plstes. But in cases of emergency
pour cold water in before the hot water i
let out, and mix the two together 60 as Ia
cool the boiler down gradually and gener-
ally, and not suddenly and locally. II q
boiler is blown of under steam pressure the
plates and brickwork are left hot. The hot
4 plates harden the scale, and the hot brick
work hurts the boiler. Cold water dashed
on to hot plates will cause severe straining
by local contraction, sometimes sufficient tc
fracture the seams.
The new dock at Cardiff, of which Lord
Butte cut the fret sod the other day, will
extend over tbirty.fve acres, exclusive Of
timber ponds, and will cost about f6O0. 600
The lock will be the largest in the world
its dimensions being 80 feet wide and SOC
feet long, while the depth of water over the
stills will vary from 26 feet to 80 feet
The dock will be 2,400 feet long and Coz
feet wide. the depth Of the water varying
between % feet and 33 feet, according to
tide. There will be timber ponds covering
eighteen acres adjoining. All the railway
arrangements and the loading and dischaI z.
ing machinery will be of the most complete
description Whez the: new dock is com.
plete there will be water area in Cardiff
basins and docks Of $50 acres, and quay.
age OF five miles.
La Lumiere Electrieue says that ID. Partz
exhibited plan of new mode of electric
lighting, at the French Electric Exposition.
The light was placed in chambers under.
meath the street and reflected through hol.
low cylinders, enameled on the inside, so as
to produce an inverted cone of rays, which
strike reflector placed at height of 40 OF
so metres above the street. Among the
advantages which are claimed by the inven-
tor are: The employment of powerful electric
foci, thus avoiding the loss which results
from the division of the current; the equal
diffusion of the light and the avoidance Of
the dazzling glare; the diminution Of the
loss of light which results from the employ
ment of translucent globes: the readiness Of
access for regulation and surveillance, and
the illumination of thick mists, which can
be penetrated with difficulty By other meth
DDS.