Cooke and Wheatstone Telegraph

Overview

It was designed by its namesake inventors, Cooke and Charles Wheatstone.

The receiver had 5 pointers, two of which were energized to point to the selected letter.

Advantages

The main advantages of this telegraph were that it is designed to be used by relatively unskilled operators. The displayed to the receiver the letter that had been sent.

Disadvantages

The main disadvantage was that is required 5 five wires to connect the sending and receiving stations. A sixth wire might also be desirable for the return current if the earth return were poor, or if the was interference from other circuits.

Another disadvantage was that only 20 letters could be displayed of the 26 letters in the English Alphabet, leaving out D, J, Q, V, X and Z.

Obsolescence

It was later found that telegraph messages could be received by sound alone, which was the basis of the 1-wire and 2-wire Morse Telegraph, which also had no difficulty transmitting the whole alphabet plus symbols as well.

Diagram

Famous Tawell Arrest

The Cooke and Wheatstone Telegraph was famously involved in the arrest of murderer John Tawell. Because this telegraph had not letter "Q", while the message contained the word "Quaker", the receiving operator had some trouble understanding that "Kwuaker" was meant to be "Quaker".

It is not clear how the other missing letters would have been transcribed:

• D - ?
• J - I ?
• Q - KW
• V - U?
• X - KS (think of sox and socks)
• Z - ?

References

External links