Evening star. [volume] (Washington, D.C.) 1854-1972, 1858-05-28
NEW PAYING. MACHINERY OF
T!tE ATLANTIC TELEGRAPH.
from the London Daily News

1HE ATLANTIC TELEGRAPH.
FFrom the London Daily News
An inspection Of the new machinery designed
for the paying out of the Atlantic Telegraph
Cable will amply repay scientific curiosity
Nothing, apparently, can work more freely and
admirably than the whole apparatus We UT.
derstand that it has been inspected by some OF
the first nechanical engineers, who express Cd
their unqualified appreciation of the arrange
ments which have been made to avoid all unto
ward accidents TO which the cable NAV be sub.
jected.
Our readers will remember that it was owing
to some defect in, or mismanagement Of the
p1ylng- out apparatus that the failure in laying
down the cable last year took place. The ten
SION 20 which the cable is subjected in passing
out OF the ship is owing to the weight of that
PORTION which has not as yet touched bottom,
aud constitutes the force by which the other
portion Is uncUilcd from the wheels or drums
ove- which ii is passed in its evolution from the
hold OF the ship. The greater this tension the
greater the speed with which it will pass out of
the ship. II means be not taken to check its
progress Mechanical aids we're devised to OBJ
tain this check, and accommodate the paying
cut OF tho cable to the rate OF Il g ships motion
these consisted of friction drums SO applied as
to retard the progress of paying out. The fric-
tlon being regulated by brakes as the ship rose
and fell with the sea the pressure on the cable
hdS necessarily lHcrcaSeu or ulmlEl-f6 L. w hen
tho swell caused any sudden descent of tie
stern of the vessel, it was necessary 10 ease the
brakes. In the old machinery the handle of
the brake could be turned so as either to in
crc1Se or diminish its power. Tho man in
charge OF the brake, Instead of turning so as to
ease 1t, Is supposed in the excitement of the
moment, to have turned it the wrong way.
linus the fatal rupture was made. To Obviate
such calamity as this for the future the
yllV mo- rnt,, La,,. 4
eicd. The brake6man can ease the retardiDg
apparatus, but can add nothing to its power
Any addition to the frctional retardation can
only be made by and with the full cognizancc
Oi the principal engineer in charge.
The friction brakes are applied to the cir
cuiniercncc Of wheels firmly attached TO the
aXieS OF the paying-out apparatus. They arc
the Sell-adJusiIng brakes invented by the inre-
niOus Mr.. APpold, 10 prevent prisoners con-
demEed under the system of crank labor from
having moro than their fair share of work to
do. 4 his cOntriyance has been adapted 10 the
paying out machinery by Mr.. Field, OF the
firm Of Maudslay, Sons & Field. The details
have been brought into working order and nu
mercu> meChaIical difficulties overcome by tho
zeal and energy of Messrs Bright and Everett,
aided by the great experience Of Mr.. Amos as
4 practical mechancian.
The payinG-Out apparatus consists of two
large wheels, the circumferences Of which arc
lndentcd by four deep grooves. Both wheels
are OF the same diameter. One is placed at a
little distance from the other, both in the same
plane and with their aXies parallel to each
other. The axles of these wheels work in a
stout ard firm frame, which is So constructed
as to resist any tendency of the cable to draw
the wheels toward each other Tho cable,
after coming out of the hold Of the ship in
which II d cOiled, Ia passed over the first
groove OF one wheel and then over Il groove of
the other until the four grooves of each wheel
are occupied. Each wheel has its circumfer.
ence passed over by four portions of the cable.
each portion OF course increasing the friction
or bite Of the cable On tho surface of the
wheel. This is sufficient to prevent the cable
from slipping over the surface of either wheel
without causing it to revolve.
Any means which can be devised for check
ing the revolution of the axle or the wheel will
retard the motion of the cable over its circum-
ference. For this purpose two friction wheels
or drums. are firmly fixed TO the axle of each
wheel. These drums, whose external circum-
ference Is Of plane iron, have a band 10 which
wooden blocks are attached, which, by means
Oh levers, can be made to clasp the surface Of
the drum. The friction brake TINS consists Of
surface OF wood pressing on a surface of iron.
with a pressure which csn be increased at the
viii oil the engineer. The clasping apparatus
Is regulated 10y weights attached al the ends of
rods. which act so as to tighten or loosen the
break. The rods work in pistons so ~ to keep
The action "f the weights always in the proper
direction, irrespective of the motion of the shin
The heat produced by the friction of tic
brake IS kept from rising to any iniuriou
height by portion of the drum revolving in a
constant supply of cold water The weights
by which the friction of the brake is regulated
are fixed to the rods. so thai they can only be
increased or diminished by the principal engi-
necr The friction or retardng force is thus
so far ,eli-adJ dJuStiBg that it can never be in
creased except by the engineer allowing addi-
tional weights to be attached to the rods With
one exception, it is constant. This exception
is. that at any instant when required the
whole frictionai power of the brake can be i'm
medtately cascd.
The cable, after passing four times around
each of the wheels of the paying out appara-
tus, passes under Il grooved wheel or pulley
the axis Of which is attached to Il weighted
rod working III Il piston. This groOycd wheel
is 80 arranged that it can rise or fiji in frame
work, according to the tension Of the cable
which runs under its circumference and over
another fixed pulley, by which it passes out OF
thc-shlp l. greater or less than the weight OF
the pulley and its weighted rod
lhe apparatus is, in point of fact, 4 dyna-
Hoiheter' winch marks the tension OF the rope
a ii Is being paid out Of the ship. This ten
sion is indicated by a pointer. which makes ON
the graduated frame Of the pulley the position
to which its axis is raised or depressed. A man
stands before this, in charge of a wheel, by
turning the spokes Of which he can immedi.
ately take off the pressure of the fixed weights
on the brake apparatus, and ease the whole
the moment dangerous degree of tension is
Indicated by the index of the dynamometer
but the apparatus under his charge cannot, by
any Peryersity OF fear or stupidity, be made a
apply any greater strain than tho engineer
may think expedient and safe. lie can thus
instantly case the breaks, but cannot commit