Preserve railway’s mechanical wonders
Letter by Dr John Elliott, The Straits Times, 26 Jul 2011.
I am delighted that a part of the KTM railway is to be preserved (“Parts of KTM railway to be retained”; last Saturday).
We should also preserve one of the old mechanical signals, several of which are to be found on the northern reaches.
These signals were mostly later replaced by electric lights (a set also visible near the Bukit Timah station) and are museum pieces. They are a triumph of mechanical engineering and exemplify the principle of levers. The weighted arm halfway up the mast was a safety feature. Should a wire break, the counterweight would fall and ensure the signal came to rest with the arm horizontal at “stop”. Crowds photographed these striking structures, which are still in working order.
Source: The Straits Times