KNOCK THREE TIMES

[hope]

One of the most important parts of a POWs life was communicating with his
Fellow captives , The first communication between isolated prisoners of war
May have been name scrawled on a piece of toilet paper with the burnt end
of a matchstick.
Notes and whispers were attempted but both wer often detected and severely
punished.

In June 1965, four POWs --Captain Carlyle Harris known as Smitty, Lieutenant
Robert Peel and Lueitenant Commander Robert Schumaker, who were imprisoned,
in the same cell in Hoa Lo, devised a simple,secretive cod.
The four men , expecting to be split up again, vowed to continue their resistance,
to do this they communicating closely would be essential.

Harris remembered an Air Force instructer who had shown him a secret code based
on a five-by-five alphabet matrix, each letter was communicated by tapping two
Numbers, the first designated the horizontal row and the secound the vertical row,
the letter W, for example, would be 5-2, the letter H would be 2-3, the letter X was
used to break up sentences and the letter C replaced the letter K.

by August 1965 most of the prisoners had been initiated, and were passing messages
By tapping.
It was said that the building sounded like 'a den of runaway woodpeckers'

Knock Three Times .. on the ceiling if you want me
Twice on the floor if the answer is no

Knock 11-14-15-11. 2-5-7-3-2. 18

Knock knock knock 999
http://973-eht-namuh-973.com/forum/view ... f=1&t=3020

[Redbeck]

Great stuff Hope, well worth the research, examination and explanation of the more practical or perhaps practiced use of numeric coded patterns outside the technology halo to the advantage of us all, thank you.

In fact Tap Codes are spread far and wide in their application; prime example the Code of Safety for Diving, in which as you will see later, 3 x 3 clusters of three taps are an important open and close statement.

However, let's get on with the detail, and I quote:

'Chapter 2
Communication
2.2.16 In addition to the communication systems referred to above, a standard bell [diving bell] emergency communication tapping code shoul be adopted, as given below, for use between persons in the bell and rescue divers.

A copy of this tapping code should be displayed both inside and outside the bell, and also in the dive control room.'

'Chapter 3
Evacuation
3.1 An evacuation system should be provided having sufficient capacity to evacuate all divers under pressure, in event of the ship having to be abandoned, and should be in accordance with the provisions of this Code'

As I mentioned the significance of three taps earlier, 3.3.3 in the table below signifies:

Communication opening procedure (inside and out [of the bell]
AND ALSO
Communication closing procedure (inside and out [of the bell]

As there is a fair sized image of the tap codes table available below, I recommend that you review the picture for a detailed description of the meaning of each element of a relatively simple but nonetheless esoteric numeric tapping code alternative.

[hope]