favorable condition without the assistance of the operator.

A larger number and greater variety of ideas can be conveyed
with greater exactness in fewer words in the English language
than in any other. Its advantage over French or German, lor
instance, is said to be from 25 to 33 per cent.

The telegraphs of the world are estimated (Hawkshaw) at
400,000 miles, at S 500 per mile = S 2(X),000,000.

The wire is now in all ca?es, except those of submarine cables,
and sometimes in cities, conveyed upon poles. In this country
any kind of available wood is used, and in passing through for-
est's the wire is frequently attached to living trees. The poles
seldom undergo anv treatment for the purpose of preserving
them. In England more pains is taken. The timber generally
employed is larch treated with sulphate of copper, or red fir
crecsoted by the Bethel process. When not sulphated or creo-
soted, they are well seasoned and then painted, the but-ends
being slightly charred to a foot above the ground line and
tarred- Each pole is provided with an earth-wire or conductor
for conveying electricity escaping from the wires in wet weather
to the earth. These sometimes project above the tops of the
poles, and serve as lightning-arresters.
1 The poles are also stayed by wire ropes connected to rods in-
serted in the ground, and in exposed positions double stays are
employed.

On railway lines the Varley double-cone brown-ware insu-
lator is emploved, and on canals and highways the single-cone
white-ware or" porcelain insulator. The wires are attached to
the insulators at every post. What is known as the Britannia
joint is exclusively employed for uniting the lengths of wire.
This is made by bending the ends of the two wires, placing
them side by side for a distance of three inches, binding them
together with No 19 wire, and soldering them.

The domestic or district telegraph is designed to connect
stores, private dwellings, or other houses in cities with a central
station, where there is an observer to attend to the messages
received- The transmitting instrument is attached to the wall
at a convenient place in the house, and connected by a wire
le.ading to the roof, with a wire leading to the station ; it is
provided with three knobs or levers, one for sounding an alarm
; of fire, another for summoning a policeman, and a third for in-
dicating that a raes.'^enger is wanted. On either of these sig-
nals being transmitted, the requirement is at once indicated
and attended to at the centnil office.

Fig. 62S8 is a maffneto-electrlc dlal-telegmph adapted forrail-
roads and private business purposes. The electricity is gener-
ated by working the treadles which rotate the armatures of the
magnota. When the crank at the front of the machine is in
upright position, as shown, the alarm from a distant station
may be received: it is t\irned to the right when desired to
traofioiit & message ; in either diagonal position the circuit is



TELEGRAPHIC ALARM.



2506



TELEGRAPHIC ALARM.




Ma^neto-E'ectric Dial- Tdegrapk.



broken, and when turned to the left the circuit is through the l

indicator oaly.

Fig. 6238. The automatic- !

alarm telegraph is .

constructed for i

*■■ thieves '' and for \

'' fire." In one

ca-;e, the shutters,

wiudowfi, and doors

are so connected

with an alarm in

an office or the bed- i

room as to spring i

an alarm if any of \

the paid objects are

tumpereJ with.

In the other case,
thermostats are
placed at all neces-
sary poiuts, and 1
wheQatanyofthe.-*e I
the heat of the room ]
or passage ri^^es a j
degree or two above
the point for which I
\.-r^ it is set, an electric [
contact U made and j
the alarm is sp'rung. |
Thefollowiug pat- j
entsof Watkiiismay I
be consulted; March I
10, 1863 ; May 10, 1870 ; January 31, 1371 (six patents) ; March ,
28, 1871; October 27, 1874.

The system of ^r^-'i^arm (Wegrap/ts, now so general in large ]
American cities, is referred to ou pige 849, and the devices on i
page ldl3, R:gister; page lylS, Kepeater.

One important application of ifle teiegrLph is for determining |
differenrifs of lougitude. For this srieuue is largely i.iJebted to
Dr. Locke, of Cincinnati, by whJDi it was succe'Sfally practiced
as far back as 1848 Cambridge 0>servatory, Mass., nas thus
been brought into direct comumnicatiou with oan Francisco by
connecting the wire with the pendnlum of a clock at Cam-
bridge, so that the main circuit is broken and instantly closed
at each oscillation ; the moment at which the circuit is broken
is noted by the observer at San Franci-^co, by a clock regulated
to local time there, which, being compared with the loc^l time
at Cambrid^^e, gives the diiference of longitude between the two
places. Many other stations, both in Europe and America,
have been connected, and their longitudes determined in this
way.

The moments of breaking and closing the circuit are practi-
cally the same at both places, the veloi-ity with which the cur-
rent traverses the wire being comparable only to that of light,
though Professor O. M. Mitchell determined that a minute
though appreciable interval of lime eUp^^ed during its passage
between two widely separated stations.

The telegraph was first used for military purposoi during the
Crimean war. 1854-55. Its application for this purpose was
greatly extended during our recent civil war, and has now be-
come systematized in the armies of Europe.

In the French army the whole apparatus is carried in a cov-
ered carriage, divided into two comp irtments, one for an office,
and the other containing a reel of wire. In the office is a table
for supporting the instrument, two accumulators, one for the
batteries, and the other for the signal-bells, and a seat for two
persons. The reel is supported on its axis in the rear compart-
ment, so that the wire unwinds as the carriage proceeds ; it
contains 3 kilometres (nearly 2 miles) of wire, and extra reel
carriages are provided, each carrying 21 kilometres (over 13
miles) of wire on 7 reels. The wire i* composed of 4 copper
threads twisted togetlier, and protected by an insulating coating
of fiber and india-rubber, so that when laid on the ground it
will sustain the passage of vehicles without injury. Poles are
used in special cases. Each telegraph -carriage is in charge of
a sergeant, two corporals, and twelve men divided into three
squads, the first of which goes ahead with the sergeant, traces
the line, cuts a trench for the wire, or makes the poles; the
second has charge of the reels, and makes the necessary splices,
and the third lays the wire or fixes it on the poles. In moun-
tainous countriea mules are substituted for the carriage ; one
carries a smill tent, a tripod table, stake, the battery, and
tools ; another two reels of wire ; a third draws a barrow which
serves as a reel-frame, which is guided by two men, who carry
it in difficult places. See TELEaR\PH-ciRiii.4.GE.

Tel'e-grapMc A-larm'. {Tckf^raphy,) A sound-
er o|)eiate<l by electro-telegraphic means.

There are many forms : —

The alarm which runs down, a detent being with-
drawn from the escapement. See Acoustic Tele-
graph, page 11.

The clicking-instruraent, operated by successive
impulses. This has grown into the ordinary tele-
graph, which is read by sound.



See also Telephone.

Although Franklin, in 1748, fired spirits by means of a spark
trant^mitti-'d across the Schuylkill, the first distinct pluu lor a
telegraphic alarm to call the atten-
tion of an operator or correspond- Fig 6239.
ent was by Schweigger, about 1811.
He proposed a pistol, charged with
a mixtureof oxygen and hydrogen
gases, to be fired by a spark de-
rived from the long electric wire
proceeding from the distant sta-
tion.

Fig. 6239 is an alarm with an
escapement, a is an electro-mag-
net ; b an armature of soft iron,
which is attracted as often and as
long as the voltaic current circu-
lates through the coil, but is pre-
vented from coming in actual con-
tact therewith by means of two
copper studs tipped with ivory.
The armature is mounted on the
short arm of a lever c, which is
normally pressed by a spring so as
to engage a stop on the wheel d,
preventing it from moving. When
a current passes through the coil, Tdegraplnr Alarm.

the armature, being attracted, re-
leases the lever Irom the stop, and clock-work mechanism oper-
ating through the scapi*-wheel d upou the pallets e causes the
hammer/ to vibrate, striking each sideol the bell g alternately.

Fig. 6240.





Electric Telegraphic Alann.



In Fig. 6240, the hammer is rung without the intervention of
an escapement, by means of a current of magneto-electricity.
The cores uf two coils a a are connected by a bar A, and serve
as keeper to the horseshoe magnet c. On depressing the lever



Fig. 6241.




Connection for Bell-Alarm.

d, these are raised from the poles of the magnet, creating a cur-
rent which passes through the coils and along the line to the
bell.

Fig 6241 exhibits the connection." for a bell-alarm a is the
battery ; b, the zinc-pole ; c, the carbon-pole ; d, the key j ey,

Fig. 6242.




Ctock-Work Alarm.



TELEGRAPH-CABLE.



2507



TELEGRAPH-CABLE.



the binding screws of the bell-magnet. When the key is de-
pressed, the biittery current is thrown upon the bell. The three
elements of the circuit may of course be separated by any dis-
tance vpithio that through which the battery is able to transmit
its current. A sounder or register may be substituted for the
be.l.

In the alarm, of which a side view is shown at B, and front
and back views at A C, Fig. 6'2-12, two electro-magnets c c, hav-
ing tlieir coils connected and wound iit similar directions, iire
joined at one end by a piece d of soft iron. At the other end is
pivoted a soft iron armature a, placed at such a distance as to
be strongly attracted by the electro-magnet when the circuit is
completed through its coils, and is connected with a detente,
which ordinarily engages a fly, but is released when the arma-
ture is attncted by the closing of the circuit, allowing a train
of clock-work, impelled by a spring or weight to operate, and
throuirh the medium of a scape-wheel and pallets, causing the
himmer /i to strike the bell ^. When the current ceases to
flow, the armature is retracted by the spring 5, again locking
the mechanism.

Tel'e-graph-ca'ble. (Electricity.) The essen-
tial fV;itniv.s of a submarine telegraph-cable are a wire
or wives for conducting and a protncting compound.
To these are added sheathing, to protect against abra-
sion or other injury, and sometimes material to in-
crease the tensioual strength of the cable. With
these conditions to meet, there have been numerous
patents in the United States and in England, but
the patents of the latter country are in such a cha-
otic condition that it is almost impossible to give an
iuttdligent idea of them. The same invention is the
suhject-m;itterof numerous patents, and the futility
of many of the devices is only exceeded by the utter
looseupss witli which they liave been lapped and piled
upon each other.

The inventions concern particularly, —

1. The arrangement of the coated wires in clusters
with protecting envelope.

2. Wrapping or enveloping in light material to
give buoyancy to the cable, and prevent the parting
of the wire when laying it iu deep water.

3. Modes of connecting and splicing the ends of
sections or lengths of wire.

4. Machinery for constructing the cable ; that is,
putting on its insulating and preserving covering
wliile the wire is paid otf from a reel, or reels.

5. Materials for insulating and modes of applying
the materials.

6. Coating and preservative materials over the in-
sulated wire, or clusters of wires.

7. Means and modes of storing.

8. Machines for payingout, registering, and laying.

9. Modes of recovering, under-running, and mend-
ing.

10. Transmitting and receiving instruments.
The wires are of copper, frequently tinned, and generally

coated with gutta-percha, but preferably with india-rubber.
The det;iils are very varied in different establishments, and for
different kind.^ of cable.

In l'^39, Dr O'Shaughnessy constructed a telegraph-line 21
miles long near Calcutta, embracing 7,0(K) feet of submerged
wire ; this was covered with cotton thread saturated with pitch
and tar.

Professor Morse is said to have laid a wire between New York
and ijovernor'.'j I.'^lind in 1842

In .^Iarch, 1845, Brooman, in England, patented the method
now universally employed for preparing gutta-percha; and in
September of the same year Bewley patented a machine for
making tubing, hose, etc., on the principle of Tatham's Amer-
ican m:ichine for making lead pipe, p;\tented in 1841.

In ISld, Mr. James Reynolds, of New York, invented a ma-
chine for covering iron wire with india-rubber, and in 1848, by
the aid of this machine, covered a wire with gutta-percha, which
was laid between New York and Jersey City.

Telegraphs of wire coated in this way were extensively intro-
duced into Prussia in 1S47-48, and in the latter year a gutta-
percha covered wire was laid across the Rhine at Cologne by
Dr. Siemens-

The first submarine cable ever laid in the open sea was laid
between Dover, Dngland, and Cape Orinez, France, in I'^rjl) It
WIS a single str:ind of wire, 27 miles in length, covered with
gutta-percha, unprotected by any outside coating, and worked
only one day. The next cable was also laid hctw^n Dover and
Cj-I/h, i:i I'jol. This cable was covered with iron wire, con-
tained 4 conducting wires, waa 27 miles in length and weighed



I 6 tons per mile. It was a permanent success. The next long
cable was laid in 1853, between Dover and Ostend, a distance of
I 80 miles, contained 6 conducting wires, and weighed 5J tons
! per mile. In 1853 a cable of 1 conducting wire was laid between
England and Holland, 120 miles, weighing IJ tons per mile.
This cable worked for 12 years. From 1S53 to 1858, 37 cables
were laid down, having a totil length of 3,700 mile.s ; of which
16 are still working, 13 worked for periods varying from a week
to five years, and the remaining 8 were t4ital failures

An unsuccessful attempt to lay a telegraph-cable between
Ireland and Newfoundland was made by the " Niagara'- and
" Agamemnon " in 1857. In the succeeding year these vessels
1 joined their cables in mid-ocean, and successfully completed
the work. On the 16th of August, a message and reply were
transmitted between Queen Victoria and President Buchanan.
After 23 days, 400 messages having been transmitted, it waa
found to have lost its conducting power.

The name of Cyrus W. Field is indissolubly associated with
the subatlaotic cable enterprise.

The cable of 1858 consisted of a

Conductor. A copper strand of 7 wires, 6 laid around 1 ;
weight, 107 lbs. per nautical mile.

Insulator. Guttapercha laid on in 3 coTeringa; weight, 261
lbs. per nautical mile.

Outer Coat. 18 strands of charcoal iron wire, each strand
made of 7 wires, twisted 6 around 1, laid equally around the
core, which had previously been padded with a serving of tarred
I hemp.

I Breaking Stratn. 3 tons 5 cwt. ; capable of bearing its own
, weight in a trifle less than 5 miles depth of water.

In 1865, it was attempted to lay a second cable. The opera-

I tion was intrusted to the monster steamer "Great Eastern,"

i which commenced the work of laying the cable on the 23d of

■ July. After a considerable length had been paid out it parted,

and the broken parts could not be recovered. This cable was

much stronger than that of 1858, being made up as follows : —

I Conductor. A copper strand of 7 wires, 6 laid around 1 ;

' weight, 300 lbs. per nautical mile; embedded in Chatterton'a

compound.

Insulator. Gutta-perchaandChatterton's compound ; weight,
400 lbs. per nautical mile.

Outer Coat. 10 solid wires, drawn from homogeneous iron,
each wire surrounded with tarred manilla rope, and the whole
laid spirally around the core, which had previously been pad-
ded with a serving of tarred jute-yam.

Brea/ciiig Straiyi. 7 tons 15 cwt. ; capable of bearing its own
weight in 11 miles depth of water.

lAns:th. 2,300 nautical miles ; actually laid, 1,896J miles.

In 1866 a second attempt was made by the *' Great Eiistern,"
resulting in perfect success. She also succeeded in grappling
the end of the cable laid the preceding year, and splicing it, so
that there were now two hues of transatlantic telegraph. The
cable employed on this occasion was similar to that of the year
before, but of somewhat greater strength, 8 tons 2 cwt., its
length 2,730 nautical miles, of which l,868i miles were laid
down, part of the remainder being employed in splicing the
cable of 1865.

The distance in each case between the two points connected
waa about 1,600 nautical miles; the depth of water nowhere
exceeding 2.7 miles.

The weight of the second laid (British) Atlantic cable was
2,740 cwt. In laying it while the " Great Ea.«tern " was going
at the rate of six knots an hour, the cable passes out at an
angle of 63° only, so that the inclined plane between the ship
and the bottom was 17 miles long. The motion of the vessel in
I rolling, etc , bad little effect ; the greatest strain never exceeded
\ one tenth of the breaking strength.

The paying-out mechanism consisted of sis grooved wheels
fitted with brakes ; the cable was pressed into the grooves by
si.K riding wheels, also provided with brakes, and kept down by
levers and weights on their shafts ; these served to keep the
cable tight on the paying-out drum, 6 feet 1 inch in diameter,
and 1 foot broad : four turns of the cable were taken around
this, and it thence passed over a dynamometer wheel, which
deflected it by a lever loaded with weights, and finally over a
' grooved wheel overhanging the stern of the ship. The appa-
ratus subsequently used was similar to this.

The fifth Atlantic cable, between the coast of Ireland and

I Newfoundland, was laid by the "Great Eastern," assisted by

j three other steamships, each fitted with laying and pi<king-up

machinery. The work was begun on the 16th June. 1873, and

\ on the 27th the " Great Eastern " reached Heart's Content,

Newfoundland, having payed out l,7r'0 miles of cable in 11 days.

This cable was made at the works of Siemens Brothers, near
London, and is composed of a thick central wire, which is
passed through a peculiar composition, and afterward sur-
rounded by eleven smaller wires, the whole being cemented
together by the composition. It is then coated with gutta-
percha, anil served with manilla fiber to the diameter of j of an
inch; the whole is then covered with ten iron wires spun on,
each wire being previously wrapped with hemp, and afterward
pnssed through two tanks, by which it is caited with tar, and
finally coiled away in large tanks until want(?d for u.'^e.

The following is a list of oceanic cables laid throughout the
world up to the close of 1874. Those marked thus * are not
working at the present time.



TELEGRAPH-CABLE.



2508



TELEGRAPH-CABLE.



Ocean Telkgi!.\1'h Cables of the World.



Length

Dale. From ,in

Miles.

1850 •Dover, England, to Calai.", France 25

18.^1 Dover, Enjrland, to Calais, Fntnt-e 25

l.%2 Keyliaven to Hurst Oastle, England... 3

IHOa Holvhcad, Wales, to lloweh, Ireland.. 65

1862 I'or't Patrick, Scotland, to Donaghadee,

Ireland 15

1852 Prinee Edward Island to New Bruns-
wick 12

1863 Denmark across the Belt 18

1S63 Dover, England, to O.stend, Belgium.. 76
1S53 Port Patrick, Scotland, to Donaghadee,

Ireland 26

1S63 'England to Holland 115

1864 Port Patrick, Scotland, to Whitehead,

Ireland 27

1.'^.64 Sweden to Denmark 12

1854 •Corsica to Sardinia '. 10

1854 •England to Holland 120

18,54 "Holyhead, Wales, to Ilowth, Ireland... 65

18.54 'Spczzia, Italy, to Corsica 110

1854 Holyhead, Wales, to Howth, Ireland.. 65
1.855 *Sardinia to Africa 50

1855 •Cape Kay, Newfoundland, to Cape

North, Cape Breton 74

1856 •Sardinia to Africa 160

1855 'Varna, Turkey, to BaIaclava,Crimea 310

1856 •Eiipatoria,Criniea, to BaLaclava, Crimea 60

18.55 *Varna, Turkey, to Kilia, Roumjinia... 179
1856 'Italy to Sicily 5

1865 •England to Holland 123

1855 •England to Holland 119

1850 "Cape Kiiy, Newfoundland, to Cape

North, Cape Breton 85

1856 Prince Edward Island to New Bruns-

wick 12

1856 •Crete to Alexandria, Egypt 350

185'! Crete to Syra - 170

1S56 St, Petersburg to Cronstadt, Russia. .. 10

1856 Across Auiazon 1115

]a57 •Sardinia to Bona, Africa l.'jO

1857 'Sardinia to Malta 600

1857 'Corfu to Malta 600

1857 'Portland, England, to Alderney 69

1S67 'Alderney to Guernsey 17

1857 •Guernsey to .lersey 15

1867 Cevlon to Ilindostan .30

1867 Cevlon to Ilindostan 30

1868 •Italy to Sicily 8

1858 England to Holland 129

1868 'England to Enuleu, Germany 280

1858 'Ireland to Newfoundland 2,0.36

1868 'Turkey to Smyrna cm .\rchipelago ... 6')5

1859 "Crete to Alexandria, Egypt 150

1859 'Singapore to H.itavia 630

1859 Denmark to Heligoland 46

1869 'Cromer, England, to Heligoland 328

1859 Isleof Mm to Whitehaven, England.. 36

1859 Sweden to Gottland 64

1859 Folkestone, England, to Boulogne,

France 24

1859 Malta to Sicily 60

1859 .lersey to Pirou, France 21

1859 'Otrarito, Italy, to Aviano, Turkey 60

1859 'Ceula, Africa, to Algesiras, Spain 26

1859 'Cape Otway, Circular Head 240

1860 Great Belt, Denmark (2 cables) 14

18110 *Dacca, Ilindostan, to Pegu 116

1860 'Port Vendres, France, to Algiers 520

1869 and 18lXI 'Suez, Egypt, to Cassire,

Egypt 256

1S60 'Suakin, Red Sea, to Cas,«ire 474

1860 'Suakin, Rod Sea, to Aden, Arabia 627

1860 'Aden, Arabia, to Hellania, Arabia 718

1S60 •Hellania. Arabia, to Muscat, Arabia... 486

1860 •.Muscat, Arabia, to Kurrachec, India. . . 481

1860 •Barcelona, Spain, to Mabon, Minorca.. 198

1860 'Minorca to Majorca 35

1860 •Iviza to Majorca 74

1860 St. Antonio to Iviza 76

1861 Corfu to Olranto, Italy, about 90

1861 'Mami to 'fripoli, Africa 230

1861 'Tripoli, Africa, to Beogazi, Africa 508

1861 'Bengjuii. Africa, to Alexandria, Egypt.. 693

1861 Dieppe, France, to Newhaven, England 80

1861 'Toulon, France, to Corsica 195

1362 Wexford, Ireland, to Aberman, Wales. 63

1862 Lowestoft, Eng., to Zandvoort,IIolland 126



Greatest




Depth m
Falhonis.


Date.




30


ISfiS


30


i.sm


20


1864


83






1864


160


1864




1K64


18


1864


15


I8I16


3


1KH5




1865


160




23


IH66




1866


150


1866


14


1866


20


1866


30


1866


80


1866


326




83


1866


800


1K66




1866


330


1867


1,500




300


186',


69


1867


30


1S67


27


1867


23


1867


23


1867


300


1868




IKt,8


14


1869


1,360




1,020
10


1869


1869


1,500


1869


i,noo


1869


1,000


1869


60


1869


44


1869


60


1869


45


1869


40


1869


40


1869


27


1869


28


1869


2,400


1869


1,100


1869


1,600


1869


20


18',0


28


1870


30




30


1870


70


1870




1870


30


1870


75


1870


10


18-0


400


1870


700


1870


60


1870


18


1870


50


1870


1,585


1870


t»


1870


g"


1870




1870


i «


1870


^


1870


S


1870


%


1870


1,400


1870


i260


1870


500


1870


450


1870


1,000


1870


335


18,0


420




80


1871


26


1871


1,650


1871


60


18', 1


27


1871



Length

From in

Miles

'Cagliari, Sardinia, to Sicily 211

'Cartagena. Spain, to Oran, Africa 130

Gwadur, India, to Elpbiustone Inlet,

India 357

Mussendom, Persia, to Bushirc, Persia 3JJ3

Bushire, Persia, to Fao, Persia 164

Gwadur, India, to Kurracbce, India .. 246

Otranto. Italy, to Aviano, Turkey 50

'Bona, Africa, to Sicily 270

Trel leborg to Uugen , Germany 65

South Foreland, England, to Cape

Grinez, France 26

Ireland to Newfoundland 1,896

Ireland to Newfoundland 1,852

Lyall's Bay to Whites bay 41

Crimea to Circassia 40

Colonia to Buenos ,\yres 30

England to Hanover 221

Cape Ray, Newfoundland, to Aspee

Bay, Cape Breton 91

Leghorn , 1 taly , to Corsica 66

Persian Gulf 160

'Kbios to Crete 200

South Foreland, England, to La Panne,

France 47

Malta to Alexandria, Egypt 925

Havana to Key West, Florida 125

Key West to Punta Russia, Fla 120

Placentia, Newfoundland, to St, Pierre 112

St, Pierre to Sydney, Cape Breton 188

Areudal, Norway, to iiirtshalts, Den-