The evening times., 1895-09-05
MOTHER ElRfH'S SETBACK
Tides and Star Dust Make edts a DH-
ference in 4 Century.
Liquid Fuel, Aluminium Machinery
Cement SplIces and Other
Wonderful Inventions.

"OTo6fiui tnt6tltiONSs
The explanation of Lord Kelvin's esti-
mate that the setback" of the earth IN
its daily rotation round its axis amounts
to twenty-five $50 nds per century, is re-
ported to be that such retardation Is owing
to the friction caused by the tides, the
latter acting as a brake, a MI such action
, is calculated, according to this same au-
hority. to be equal in weight to some
100000 tons applied o n the equator. Other
causes, he says, have also to be taken into
account, as, for example, the increase in
IN the size of the earth, due to the falling on
it Of mcteoric dust, which. If deposited at
The rate OF one foot In 1000 years, would
produced the observed re tardatien by
Itself. Further, such a phenome non as the
annual growth and melting of snow and ice
1T the poles, by abstracting water from the
other parts of the ocean, Introduces irreg-
u!ariues into the problem. the abstraction
acceierating the earth's motto n and the melt
ing. by restoring the water. retarling it.
Again, as opposed to the rctardjng forces,
&. is urged that there is to be taken into &c.
gradual sinki ns of the earth by cooling
this, however. being not more, perhaps,
than o ne six -thousa ndth part of the rctarda-
tion due to tidal friction.
Some OF the best engineering authorities
express the opinion. In regard To spraying
and burning liquid fuel. that the great Sc
cret OF success SEEMS To lie In so arrang-
| L.. ft,as NIL NOT v,,,f
itself out and prevent the oil from being
properly consumed. 1t is urged that. when
petroleum spray Is directed into a furnace
high up. IL cannot burn. because the upper
part OF the fire box contains little OF no
free OK ygcn: the spray Is driven uncousumed
through the flame, strikes the bridge or
fire stone. and runs down 1t, to be burned,
usually badly, below the Jet of oil should
enter the crate bars, but the precise height
is matter of adjustment. involving spe-
cial knowledge. As regards spraying being
effected by steam, an objection to the
practice is that the quantity used is very
considerable. and represents great waste
of fresh water, To be made up again for
the 81 ke of the boilers, at least in the case
of sea going steamers. The use of Cum
pressed air is by some thought to be pref
cradle, but both steam and air may be su-
perseded by driving the oil in through very
fine nczzles, needed il desirable, under
heavy pressure-a device which has been
employed in the case OF oil engines with
mucn success. though its value in respect
TO furnaces is yet to be thoroughly tested.
Austrian ingenuity is reported as having
been successfully applied by NJ. Faure,
manufacturer OF plush and velvet power
looms. who has the whole of his cutting
appa ratus made of aluminium, and is said
to find various advantages resulting from
this plan, especially in respect TO lightress
and strength. In older methods it Is re-
Ma rked. tile weight Is matter OF objection,
the speed of the apparatus being thus con-
sidera bly, interfered with. as well as
its stability, drawbacks which repeatedly
led to unsatisfactory work. Again, the
appa ratus previously relied upon worked
backward with the help of an endless
catgut string, and was thus exposed TO
serious shocks, so that it was found de-
sirable to abandon steel and iron and re-
sort to hard wood: but while the weight
was undoubtedly diminished to some ex-
tent in this manner. il still renlai.ed too
great. the parts being found to easily
become altered in their position and shape,
so as to soon wear away. On the other
hand. the properties of aluminium are such
as to avoid such liabilities in its use. the
substance being both light and stable.
One of the most rema rka BILE mechanical
constructions of its kind is the immense
centrifugal pump at the pumping station
at LyDden. Holland. 1t is of the vertical
compound, single-acting type, the high
pressure cylinder being placed inside the
low-pressure cylinder, the piston of which
is OF apnular form. The common crosshead
is connected to eleven rocking beams of
the same shape as the walking beam of a
steamboat, these beams being piyoted at
the walls of the circular building in which
the engine is set UP, their outer ends pro-
JectiDg from the building like set of
spOkes and connecting with the pump.
The engine is OF course adapted to pow
erful work. The pump has an inlet fifty
eight inches in diameter and is driven at a
speed of about one hundred revolutions a
minute by n vertical directing compound
pump designed to furnish some five hundred
horsepower. Economy trials, lasting eight
hours or more, have shown a Use of twenty
eight pounds of steam per water horse
power per hour, and the coal consunled-
an inferior quality-was 4.16 pounds per
hour.
The cement splice is. according to a writer
in the Wood Worker, the most perfectly sat
isfactory method OF joining together the ends
OF belt. In leather betting such a splice
is comparatively easy to make, as the ends
of the belt may be Scarfed to a thinedge with
an ordinary iron bench plane, but before
rubber belts can be thus treated it is neces-
sary TO cut them down in steps or sections.
A four-ply belt may have three sections, one
thickness of the canvas being cut back sew
eral inches. another thickness cut back two
thirds OF the distance, third thickncSs-ut
back one-third of the distance, while a
thickness of canvas is left untouched at the
bottom, the other end of the belt being
treated In the same manner, 50 that when
the ends are brought together the sections
left ON one end will replace those cut on the
other end of the belt. To obtain the best re-
suits 1t Is recomme nded that the belt be put
into press a after the operation of cementinc,
but in the absence of that tool the belt may
be laid fiat upon board and fastened b =
driving a number of shoe pegs through the
belt into the board, allowing it to remain
thus suntil the cement has set, and then closely