Daily globe., 1880-06-27
SCIENTIFIC.


driving piles, lately introduced in London,
seems to have proved quite successful. Ac-
cording to the Engineer, these piles which
are tubular, can be made of either cast or
wrought iron, and the thickness of the metal
can be proportioned to suit the varying cir
cumstances of construction; the lower end
of the pile is made solid and pointed, is gen.
orally of wrought iron and steel tipped !; the
piles are also formed in sections, screwed
together by strong steel sockets or joint
covers, which are barrel shaped on the out
side in order to diminish friction when be-
ing driven. Instead of blows being deliy.
cred on the head of the pile, the driving
force is expended just where it is needed,
namely, at the point, and this result is at
tanned by using an elongated cylindrical
driving weight, which travels easily inside
the tube; the weight is raised by means of
rope or rods, and is allowed to fall on the
hat head of the solid point, the pile thus
forming its own guide for the driving
weight. The effect of each blow is to drag
rather than drive the pile down; the point
is swelled, and of sufficient diameter to eff
feet clearance for the joint covers, which
have to follow it down, the whole operation
being one of entire simplicity.
IHE discovery was made, some time ago,
that crude ammonia water-or gas liquor,
as it is called with great promptness in
extinguishing fire in tar distilery. It is
now recommended, as utilizing the import
ant fact in question, that owners of cotton
mills and of tar works, varnish factories,
&C., should have on their premises stock
of about 1000 gallons of this gas liquor
stored in tank or old boiler, mounted upon
brickwork, and at such an altitude as to give
pressure enough for a good jet service in
case of fire. The readiness-it is urged
with which jet of this liquor, thrown into
a burning room, would act, the space being
so enclosed, when the action is so powerful
In comparatively open space, and with such
a refractory substance as burning pitch,
must be obvious. 1t is assumed, too, that
the extinguishing power of the liquor would
be increasedly called forth by more in
tensely hot fre-for, in this case, in all
probability, the ammonia would be decom-
posed, and the generated hydrogen and nj
trogen gases would help to swell the volume
of non-supporting gas, displacing the air,
and so choking out the combustion.
In enumerating the dangers to which
ocean cables are liable, DIR. Preece says that
the chief cause of accidents, next to that of
anchors, is due to the abrasion of the cables
on rocky bottoms. The bottom of the sea
is frequently of an undulatory nature, and
the cable remains suspended from point to
point, and at such points the wire becomes
chafed and worn away, and speedily decays;
sometimes the cables rest on corrosive
stones, copper ores and ironstones, when
corrosion sets in and causes the cable to
speedily fail; volcanic action sometimes
damages cables, as also rock slips; icebergs,
too, frequently carry large pieces of rock,
which fall to the bottom when the iceberg
thaws, and in their descent are liable to fall
across cable; finally, and in addition to
lightning, earth currents, &C., there are also
faults due to imperfect joints, which are ow-
ing to accidents of one kind or another, that
pass inspection during the process of
manufacture, but which slowly develop
themselves after submersion or lapse of
time.
The action of sewer gas on lead and zinc
has been made matter of close investiga-
ton by chemists, the general conclusion be-
ing that, though it is impossible to deter
mine, otherwise than by experience and OBJ
servation, how long an ordinary lead soil
pipe or trap will resist the action of sewer
gas before perforation takes place, it is GER
tain that thick one will do SO much longer
than thin one, and it is equally true that
one efficiently ventilated will serve nearly
double the time of one continuously air
bound Again, an examination of the ac-
ton of sewer gas upon zinc rhones on the
caves of buildings where it was striking on
the under part, has shown that, in the
course of couple of years or SO, consider
ably large holes had been eaten completely
through, proving that such material cannot
long Withstand the effect of the gas. Lead
is, of course, more durable than zinc, but
the difference is only question of degree,
the inevitable difficulty presenting itself with
the lapse of time.
THE refuse of oats, it is found, may be
advantageously used as material for paper
manufacture, the object being effected by
first immersing the oat husks in water In a
tank, SO as to float off all foreign seeds, &C.,
which would materially deteriorate the quail
ity of the paper. The oat husks are then
allowed to settle, and the surface scum and
floating seeds are drawn of. by an overflow
pipe at the top of the tank, or otherwise re-
moved after which the water is completely
drained from the husks by waste-water
pipe at the bottom of the tank, and beneath
q perforated false bottom, or fitted with
strainer which retains the oat husks. Tho
latter may be left to steep in the water for
from FIVE to ten hours after or during the
removal of the scum, as this sleeping, by