Miscellaneous: Operating Equipment & Practices

Maintenance of the Permanent Way: misc_equip247

Photograph of a Hallade Recorder and an extract from a London Midland and Scottish Railway handbook (dated 1934), which describes the instrument and details how the Hallade Recorder was to be used.

The photograph shows at the bottom left, the clockwork spring mechanism that powered a chain drive. Above this are two rolls, the lower of which contains the chart paper and the other carbon paper. The recording needles press on the carbon paper which leaves a trace on the chart paper below. Three needles are attached to the pendulums on the right, each of which can move in one direction allowing transverse, horizontal and vertical movement to be recorded as separate lines. A fourth needle was operated remotely by an air pressure switch and this was used by a spotter to add location markers to the chart paper. On the Great Western Railway a fifth needle recorded the operation of the Whitewash device. The Hallade Recorder was protected in a robust case and positioned at the most sensitive location, which was normally directly over a coach bogie.

Robert Ferris

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