Adrodd fel Amhriodol
Testun Gwreiddiol (Anodiad: EAW007598 / 963327)
'
Ramp between the running rails, a part of the G.W.R.'s fog warning equipment. When the distant signal is at clear an electric current is passed to a locomotive by way of a contact shoe which is forced upwards and a bell is sounded. If at caution, the ramp is dead and the upward action causes the brakes to be applied. This system was superseded after the Harrow disaster with one that did not rely on mechanical contact but magnetic. '
