TheCodeBreakers
With cipher pulses 10100, and the key pulses 00110, the plaintext would
be:
ciphertext 10100
key 00110
plaintext 1 0 0 1 0, or d.
To combine the pulses electrically Vernam devised an arrangement of
magnets, relays, and bus-bars. Since encipherment and decipherment
were reciprocal, the same arrangement served for both. He fed the pulses
into this device from two tape readers—one for a keytape, the other for
the plaintext tape. The mechanism closed a circuit, resulting in a mark,
when the two incoming pulses were different, and opened a circuit,
resulting in a space, when they were the same. This output of marks and
spaces could be transmitted just like an ordinary teletypewriter message
to the receiver. Here the Vernam apparatus sub-
tracted out the key pulses, which were supplied by an identical
keytape, and recreated the original plaintext pulses. These it would
annaabi.ee 
