Photograph by Simon Lowe, 1/5/00
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THE SIGNAL BOX |
OVERSEAS |
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Photograph by Simon Lowe, 1/5/00 |
Castlerock can now claim the distinction of being the last regularly staffed mechanical signal box in Northern Ireland. It controls a crossing loop and level crossing on the single line from Belfast to Derry/Londonderry. The up starting signal, a lovely example of a somersault signal, is visible in this picture. All the surviving semaphores on the NIR system are of the somersault pattern.
The signal box is of simple prefabricated construction, provided here during the nineteen-seventies. It was apparently intended only as a temporary installation.
 Photograph by Simon Lowe, 1/5/00 (Click on the diagram to view a larger scale image) |
The signal box diagram is drawn to a very early style, as witnessed by the way that the points have been depicted.
 Photograph by Simon Lowe, 1/5/00 |
There is a 10-lever Railway Signal Company frame inside, installed here
second-hand. The loop points have economical FPLs, hence levers 5 and 6 are
painted half blue and half black. The distant signal levers are painted yellow
in accordance with standard practice throughout the UK. The distant signals at
Castlerock, however, are no longer worked.
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 Photograph by Simon Lowe, 1/5/00 |
The section to Londonderry is worked by key token (above left), the instrument seen here being unusually painted green. The key tokens themselves were given very small handles so as to minimise their weight for use with token exchange apparatus. Because the handles are not large enough to the bear the name of the section in full, they are simply stamped 'CK'/'LY'. The key token circuit to Derry operates over radio channels.
The single line section to Coleraine is worked by Tyer's No.6 tablet (above right). One of the key tokens for the Derry section can be seen resting on top of the tablet instrument. The leather pouch has clearly seen better days.
A Manson's token exchanger (right) still stands at the Derry end of the
down platform, although its detachable exchanging head has been taken away. The
down starting signal, number 4, is visible a few yards in advance.
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Comments about this article should be addressed to Simon Lowe |
