How can a message be sent with dots and dashes?
Each letter of the alphabet is represented by a series of dots and dashes, called the morse code. A Dot is a short pulse of power. A Dash is 3 times longer. The person sending the message has a switch which he pushes down to make the connection, and it springs up again when he releases the pressure. This is called a Key. At the far end of the line a small device with an electro magnet is connected via cable to the sending key, and there is also a battery in the circuit. When the sending key is pressed the receiving device called a sounder makes a click noise. The person at the receiving end can recognise the long and short clicks, and thus read the message.
