THE SIGNAL BOX

OVERSEAS

LINCOLN
New Zealand Government Railway

by John Hinson

Levers at Lincoln
Photograph from the collection of Dr. J W F Scrimgeour

These four levers are hard to classify as a signal box by any stretch of the imagination, but the picture is included to illustrate how basic the signalling could be on lesser freight-only branch lines. In the 1943 NZGR Rule Book a Signal Box is defined as: "Any place where signal levers are fixed; or where no signal levers are provided, the place where the safe-working appliances are located".

A branch turns off the Christchurch to Dunedin main line at Hornby, not too far from Christchurch, and this freight only line splits at Lincoln for routes to Little River or Southbridge. The 1952 timetable shows just one train a day to Southbridge and another to Little River. Tablet instruments were in use between Hornby and Lincoln, with Open Section working on the other two sections. There was an Officer permanently in charge at Lincoln.

Interlocking between the levers is provided by manually sliding the curved plates between the levers. All but one are released by Wood's Keys, and this would provide the interlocking between the signal levers and the point levers, which would have been located by the points they operated. The right-hand lever requires two keys to be operated. S P Wood was an employee of McKenzie & Holland who presumably invented (or copied) the device, for it is similar in many ways with the List & Morse system found in India.

As far as can be seen, the only factor that would secure the levers in the reversed position is gravity(!) - the adjustable weights on each lever seem to be for this purpose.

About the photographs

Additional noted by David Castle.



Comments about this article should be addressed to John Hinson