To telegraph from one place to another it is necessary to stretch between the two places a wire, over which the electric current may flow. Iron wire is generally used, because it is stronger and cheaper than copper wire. In the United States, wires arc usually stretched upon high poles. As the electricity would run down the poles to the earth if the wire touched them, the wire is fastened to a glass knob. Glass being a non-conductor, the electricity is thus insulated and flows freely between the places connected by the wire.

Fig. 97.   A Telegraph System.

Fig. 97. - A Telegraph System.

Figure 97 shows the actual arrangements of a telegraphic system. If the operator at one end of the line desires to send a message he opens the switch connected to his key, which is always kept closed except when sending a message. He then begins to operate his key. Every time he touches his key he closes the circuit and the electricity flows through the line causing his own sounder and the one at the other end to click. Because of the great resistance to the current, the electricity by the time it reaches the end of the line is so feeble that it is necessary to place in the local circuit a battery and a second electromagnet, called a sounder. On the main line there is another electromagnet, called a relay. This has a greater resistance, due to its fine wire, than the sounder, which has a small resistance.

When the telegraph operator at one end of the line presses on the key so as to close the circuit, the magnets at the other end of the line become magnetic, the end of the lever is attracted and drawn down by the magnets, the other end is pushed up and the steel point presses against the paper and dents a line in it. This line is made so long as the key is kept pressed down in the sending office.

As soon, however, as the sending operator takes his fingers from the key, the circuit is broken. The magnets in the register at the receiving station then lose their power on the lever, the end drops down, and a blank space is left on the paper. When the operator in the sending station taps on the key so as to close the circuit only for an instant, a dot or very short line is made on the paper in the receiving station as shown on the table below. By pressing on the key a little longer time, or not at all, the operator can make dots, lines, or blank spaces on the paper in the receiving station. By putting together these lines and dots in different ways all the letters of the alphabet may be made, so that any kind of a message may be sent.

The alphabetical application of the dot-and-dash code invented by Morse was made in 1837 by Alfred Vail, though it is universally known as the Morse alphabet. This alphabet, which is used in the United States and Canada, and in a modified form all over the Continent of Europe, is made up wholly of dots and lines, the letters most used having the simplest symbols.

Morse Alphabet

American

a

269 Steps In Telegraphing 100

n

269 Steps In Telegraphing 101

b

269 Steps In Telegraphing 102

0

269 Steps In Telegraphing 103

c

269 Steps In Telegraphing 104

P

269 Steps In Telegraphing 105

d

269 Steps In Telegraphing 106

q

269 Steps In Telegraphing 107

e

269 Steps In Telegraphing 108

r

269 Steps In Telegraphing 109

f

269 Steps In Telegraphing 110

s

269 Steps In Telegraphing 111

g

269 Steps In Telegraphing 112

t

269 Steps In Telegraphing 113

h

269 Steps In Telegraphing 114

u

269 Steps In Telegraphing 115

i

269 Steps In Telegraphing 116

V

269 Steps In Telegraphing 117

J

269 Steps In Telegraphing 118

w

269 Steps In Telegraphing 119

k

269 Steps In Telegraphing 120

X

269 Steps In Telegraphing 121

1

269 Steps In Telegraphing 122

y

269 Steps In Telegraphing 123

m

269 Steps In Telegraphing 124

z

269 Steps In Telegraphing 125

International

a

269 Steps In Telegraphing 126

n

269 Steps In Telegraphing 127

b

269 Steps In Telegraphing 128

0

269 Steps In Telegraphing 129

c

269 Steps In Telegraphing 130

P

269 Steps In Telegraphing 131

eh

269 Steps In Telegraphing 132

q

269 Steps In Telegraphing 133

d

269 Steps In Telegraphing 134

r

269 Steps In Telegraphing 135

e

269 Steps In Telegraphing 136

s

269 Steps In Telegraphing 137

f

269 Steps In Telegraphing 138

t

269 Steps In Telegraphing 139

g

269 Steps In Telegraphing 140

u

269 Steps In Telegraphing 141

h

269 Steps In Telegraphing 142

V

269 Steps In Telegraphing 143

i

269 Steps In Telegraphing 144

w

269 Steps In Telegraphing 145

J

269 Steps In Telegraphing 146

X

269 Steps In Telegraphing 147

k

269 Steps In Telegraphing 148

y

269 Steps In Telegraphing 149

1

269 Steps In Telegraphing 150

z

269 Steps In Telegraphing 151

m

269 Steps In Telegraphing 152

Morse Numerals

1

269 Steps In Telegraphing 153

6

269 Steps In Telegraphing 154

2

269 Steps In Telegraphing 155

7

269 Steps In Telegraphing 156

3

269 Steps In Telegraphing 157

8

269 Steps In Telegraphing 158

4

269 Steps In Telegraphing 159

9

269 Steps In Telegraphing 160

5

269 Steps In Telegraphing 161

0

269 Steps In Telegraphing 162

1

269 Steps In Telegraphing 163

6

269 Steps In Telegraphing 164

2

269 Steps In Telegraphing 165

7

269 Steps In Telegraphing 166

3

269 Steps In Telegraphing 167

8

269 Steps In Telegraphing 168

4

269 Steps In Telegraphing 169

9

269 Steps In Telegraphing 170

5

269 Steps In Telegraphing 171

0

269 Steps In Telegraphing 172

Morse Punctuation, etc.

Period,

269 Steps In Telegraphing 173269 Steps In Telegraphing 174

Comma,

269 Steps In Telegraphing 175269 Steps In Telegraphing 176

Interrogation,

269 Steps In Telegraphing 177269 Steps In Telegraphing 178

Exclamation,

269 Steps In Telegraphing 179269 Steps In Telegraphing 180

Colon,

269 Steps In Telegraphing 181269 Steps In Telegraphing 182

Semicolon,

269 Steps In Telegraphing 183269 Steps In Telegraphing 184

&,

269 Steps In Telegraphing 185