Water Depth Recorder, 1895, Old Pumping Station.

The depth of water on the pump well, below the engine room, was continuously recorded on the paper chart by means of the pen which was moved up and down by a cord wound round the wheel on the lower right of the instrument. This cord, now removed, was attached to a float on the surface of the water in the well below. The second pen, which is a later addition, records the boiler pressure. It was fitted to avoid conflicts between the driver and the stoker. The first duty of the oncoming shift on Monday morning was to fit a new chart and wind the clockwork mechanism. Manufactured by Glenfield Co Ltd, Kilmarnock, 1895. This is one of the instruments preserved at the Cambridge Museum of Technology.