The Londonderry sifter. (South Londonderry, Vt.) 1883-19??, 1890-02-06
SCIENTIFIC AND INDUSTRIAL.

A wash made of the water in which
potatoes have been boiled is certain
means of destroying insects on animals.
A thorough washing out with clean
water will often prove the best cure
for foaming boiler. A little common
soda may be added where grease is sus-
pected to be the cause of foaming.
The watercress is plant containing
very sanitary qualities. A curious
characteristic of it is that, il grown in
ferruginous stream it absorbs into itself
five times the amount of iron that any
other plant does.
1t is stated that as coal is burned in
the furnaces of locomotives on the Cen
trail Pacific Railroad there is a waste of
from so to rs per cent. That is, it the
heat could all be utilized it would do al
most twice what it now does.
A student in Germany recently sued a
physician for having hypnotized him
against his WILL At the hearing of the
case witnesses for the plaintiff behaved
in the most extraordinary manner, their
testimony, in fact, being utterly nonsen-
steal The court became quite bewild
cred, and great confusion ensued, until
it was ascertained that the witnesses were
being hypnotized by one of the counsel
engaged in the case.
The essence of the invention of the
"sliding railway" which was the sensa-
ton of the Paris Exposition, is the sub
stitution of thin film of water, over
which the vehicle slides, for rolling
wheels, the film being maintained by
hydrostatic pressure, and propulsion by
successive jets of water under pressure,
acting against rib of buckets extending
under the whole train, thus dispensing
with all locomotive power.
The big guns turned out by the Eu-
glish arsenals are now fitted with u de-
vice to facilitate firing at night. The
ordinary sights are illuminated by
small incandescent lamp, the rays from
which, passing through lens, are con-
verged, so that only minute point or
line of sight is obtained. By means of
an adjustable resistance the light can be
moduated to suit the degree of darkness
of the night or the eye of the observer.
One of the many fields of usefulness of
aluminium is in the manufacture of ship
plate. Ten per cent. of it added to iron
makes plate of great strength, taking
and retaining high polish and possess
ing the eminently valuable quality of be-
ing absolutely proof against the corrod-
ing action of sea water and the adher-
ence of sea grass, barnacles and other
similar growths Gun barrels can also
be made of this alloy that will neither
rust nor lead in use.
An automatic machine for making
horseshoe nails has recently been brought
out. Wire is coiled on reel on the top
of the machine, which cuts off, stamps,
points and heads the nails without any
hand assistance whatever. The receiv-
ing box only contains perfect nails, for if
there is any hitch in the working the ma
chine stops of itself, and points out by
means of an index where the fault oc-
ours A few moments only are required
to remove the offending nail, land the ma
chine starts again.
The method of constructing the foun-
dations of the great drawbridge over the
Thames at New London, Conn, is of ex-
ceptional interest. Timber curbs were
constructed, which were sunk eighty feet
into the bed of the river, the bottom of
which was soft mud for this depth. The
mud inside the crib was excavated, and
the piles driven into the solid ground
then obtained. The heads of these piles
where then bound together with con-
crete, on which the masonry of the pier
was finally erected.
Moles on the face are now being sue
cessfully treated by the use of sodium
ethylate. The mole is painted with the
sodium ethylate, a fine glass rod being
used. When the mole has vanished
look ethylate is gently rubbed in with the
glass rod, to make it penetrate more
deeply. The mole turns nearly black,
and hard crust forms over it, which is
nearly three weeks in becoming de-
tached When it comes off the mole is
much lighter than before, and this treat
ment can be continued until the mark is
scarcely noticeable.