CLOCK No. 15


P.O. ENGINEERING DEPT.
ENGINEERING INSTRUCTIONS
MISCELLANEOUS
TIME
D 1252
Issue 1, 27/10/38

WATCHMAN’S PORTABLE TELL-TALE CLOCK
“Clock No. 15”

1. Description
”Clock No. 15“ is a portable tell-tale clock which has been provided in large P.O. buildings for checking the times at which the night patrol reaches certain points in the course of his rounds. At these positions a numbered registering key is fastened to the wall, etc., by a chain. This key, when inserted in the portable recording clock carried by the patrol, causes the number of the point and the time to be recorded on a paper roll or disk inside the clock. There are three types of tell-tale clock in use, one of which, with the key, is illustrated.

2. Supersession
The clock is now obsolescent and will not be installed in future buildings. It has been superseded by an electrical system (see D 1251).

 
 
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Last revised: February 07, 2011

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