More than a quarter
of a century has elapsed since the Atlantic was first spanned by an electrical
conductor, and few of our young readers will be able to recall the disasters
encountered by those plucky electricians who conceived the gigantic scheme
of connecting the Old World with the New.
So far back as 1843
Professor Morse expressed his conviction that an electric current could
be conveyed across the Atlantic; but it was not until that enterprising
American, Mr. Cyrus Field, began to form a company in 1856 that the general
public heard anything about the ideas of the men of science; and although
very little opposition was encountered as compared with the mountains
of popular prejudice which George Stephenson had to beat down when he
was projecting his great railway schemes, not a small section of the British
public pooh-poohed the idea of an Atlantic telegraph.
The capital was
raised in England and America, and the paying-out of the first Atlantic
cable commenced on Friday, Aug. 7, 1857. On Tuesday, Aug. 11, the cable
broke in 2,000 fathoms of water, when about 330 nautical miles had been
laid. The originator of so great an undertaking was not discouraged even
at this disaster, and arrangements were soon made for a fresh supply of
cable to replace the lost portion. In 1858 the whole of the cable was
successfully laid, and her Majesty and the President of America exchanged
messages. There were great rejoicings in both countries; but, after working
tolerably well for a few days, a fault in the conductor decided the fate
of the cable. Half-a-million sterling was sunk never to be recovered,
and the shareholders were on the verge of despair.
One man alone refused
to “say die,” and that was the indomitable Cyrus Field. He agitated
the question of another cable; and a second company was started in 1862.
The firm of Glass Elliot (now the Telegraph Construction and Maintenance
Company) agreed to supply the new cable for £700,000. The greatest
care was taken in its manufacture, and on June 14, 1865, the Great Eastern
left the Medway for the Nore carrying 7,000 tons of cable, 2,000 tons
of iron tanks, and 7,000 tons of coal. At the Nore Dr. Russell states
she took in 1,500 additional tons of coal, which brought her total dead
weight to 21,000 tons! On the 2nd of August the cable snapped, and another
half million was consigned to the mighty deep. The length of cable paid
out was
1,186 miles, and the distance from Heart’s Content, Newfoundland, 606.6
miles. Several attempts were made to recover this cable, but the picking
up machinery was not equal to the occasion, and the enterprise was abandoned.
Another cable was ready in twelve months time, which was laid by the Great
Eastern without a hitch, and on the 2nd of September, 1866, the lost ’65
cable was picked up
and completed six days later!
This brief record will give the reader some
idea of the difficulties encountered by the pioneers of Ocean Telegraphy,
and when we hear of a cable being laid across the Atlantic in two or three
weeks without anything unusual occurring, we ought to feel grateful to
that band of persevering electricians who, by repeated failures and disasters
enough to shake the courage of any but the Anglo-Saxon race, discovered
the way to make and lay those deep sea cables of which we are so justly
proud.
In 1869 a cable was
successfully laid from Brest, in France, to St. Pierre Island. In 1873
a cable was laid from Ireland to Newfoundland, and in 1874 two cables
were laid, one for the Anglo-American Company, and the other for the Direct
United States Company. Then the Compagnie Francaise du Cable Transatlantique
laid a cable in 1879; and the two last cables were laid by the American
Telegraph and Cable Company in 1881 and 1882.
At the present time
two new Atlantic cables are in course of construction at the works of
Messrs. Siemens Brothers, Woolwich. These lines will be owned by two American
millionaires - Messrs. Bennett and Mackay. Two or three other gentlemen
have shares in the undertaking, but the greater portion of the capital
has been subscribed by the above-mentioned millionaires. Believing that
a brief description of the construction of the new cables would interest
the readers of the TELEGRAPHIST, we visited the works of Messrs. Siemens
Brothers a few days ago, and obtained a sight of the process of cable
manufacture.
The conductor or
“copper centre” of the deep sea section is formed of thirteen
wires spun into a strand. The copper of which the conducting wire is made
is selected with the greatest care The centre wire is about one-tenth
of an inch in thickness. The twelve thin wires are bound over the central
wire by a small stranding-machine, which grasps the principal wire as
it is driven through an orifice, and fastens the twelve minor wires around
it. There are ten stranding-machines at work upon this cable, and these
can together turn out fifty miles of copper conductor per diem. These
wires are tinned, and when the copper strand leaves the machine it is
covered with india-rubber, which is warmed into a paste and put on by
pressure. The cable now resembles ordinary thick g.p. wire, and it is
wound on drums in three knot lengths.
The next process is to cover the
cable with jute, securely bound with four thin yarns. An ordinary observer
would mistake the cable for common rope after it receives its coating
of jute. There is now a stoppage in the process; the cable is coiled into
tanks filled with water, where it remains for two or three weeks. At frequent
intervals it is subjected to the most delicate electrical tests, and if
a fault is discovered, no matter how slight, it is not allowed to pass
unnoticed. The cable is jointed from tank to tank, and great care is taken
in this part of the operations, for a bad joint may lead to a fatal disaster
after it reaches the bottom of the sea.
At the expiration of its period
of primary submersion, the cable is removed from the tanks and got ready
for the sheathing process. The sheath consists of twenty-four steel wires.
Each coil of the sheathing-wire is subjected to a very severe test; the
two ends are cut off, and a strain is put upon them equal to 700 lb. If
the wire breaks before the dynamometer registers the required strain test
the coil is rejected. We were informed that the sheathing wire is a sort
of Bessemer steel, and it is said to be of a quality superior to any which
has hitherto been used in the manufacture of submarine cables. As each
portion of the cable receives its binding of twenty-four steel wires,
it passes slowly over a reservoir of molten compound, and the black liquid
is poured upon it, filling up all the interstices. Onward it goes over
the rollers, and next receives a coat of twenty-one manilla yarns. It
then passes over another compound trough - and its covering is instantly
changed from brown to black. Rolling on its way, it is now supplied with
a covering of Russian hemp, then another shower of compounds, and the
work is finished.
The cable does not, however, stop here, but passes over
numerous rollers until it reaches the tank ready for its reception, where
it is coiled pending the arrival of the cableship. To prevent stickiness,
each coil is covered with whitewash, and the tanks are filled with water.
Some of those tanks are of enormous capacity. We saw one which held 500
knots of cable, and we were informed that the tanks onboard the cable
ships were quite as large, if not larger. In viewing the works of Messrs.
Siemens Bros., we were struck with the perfect order which reigned in
every department. The telegraph works of this great firm cover 7½ acres
of ground, and no less than 2,500 men are employed in the manufacture
of cables and telegraphic apparatus.
That our enterprising
cousins across the water should have to send to England for cables, speaks
volumes for the electrical progress of the old country. There is no need
to write a laudatory notice on the eminent firm of Siemens Bros.; their
reputation is world-famed, and for us to say that their work is perfection
would be like “painting the lily,” or “gilding refined
gold.” We can, however, add that the excellence of their work is
only equalled by the courtesy of their officials, and we are pleased to
congratulate the firm on possessing so careful and conscientious a servant
as Mr. Reis, the gentleman who was appointed our guide last Friday afternoon.
