Dirty silver dials having enamelled figures are cleaned in a different way from those having painted figures. If the figures are enamelled - and this can be ascertained by touch-i g them with the point of a graver - the dial may be heated over an alcohol lamp, and then scoured with pulverised pumice stone applied with a brush or by the fingers. Boiling for a few minutes in a copper cup containing chemically pure sulphuric acid diluted with twice its quantity of distilled water will render the dial snow-white without in the least injuring the enamelled figures. Rinsing in hot water and drying in hot sawdust completes the operation. If the dial has painted figures, the use of heat and acid are out of the question, and very careful handling is necessary if the figures are to be preserved. The cleaning or whitening may be performed by rubbing on the dial a thin paste of precipitated chalk and distilled water. The operation will be a lengthy one, but will be satisfactory if the necessary care is taken.