Dials may be made of any material, wood, stone, slate, iron, brass, copper, and coloured or semi-opaque glass. Copper dials possess many advantages, and these have been of late years preferred, except where more ornamental dials are required, in which case slate and skeleton frames are used with good effect. The large dial of my great clock which was placed over the principal entrance of the International Exhibition Building in the Cromwell Road was of slate, elaborately enamelled with white and gold on a blue ground. Another kind of dial having a good effect is that erected by myself some time since for Sir Moses Montefiore, at the Synagogue, Ramsgate, consisting of a skeleton or framework of iron fitted with Minton or encaustic tiles. A dial such as this can thus be made with comparatively little expense during the erection of the tower, and the architect can then, as I have said, design it so as to be in keeping with the edifice; the Minton tiles have also the advantage of being almost indestructible, and of being made of any pattern or colour. The chief points to remember are that the dials should be slightly sunk in the centre so as to allow the hour hand to traverse in the sinking point close to the disc and the figures, and especially that the dial should be made large enough to distinctly show the hour. Properly the dial should never be less in diameter than one-tenth of the number of feet which it is distant from the ground, and in all cases where it is possible I should recommend it to be much larger than this. The dials of St Paul's and Westminster are larger than they would be under the above rule, and they are certainly not too large. As to the colour of the dials, figures, and hands, there is not much choice; dark ground and gilt figures, or white ground with black figures, or a skeleton frame with gilt figures are the chief in use. In the white semi-transparent dials with opaque figures used for illuminated clocks, the time, which is seen with sufficient distinctness by night when the light is behind the figures, is not as clearly indicated by day. To remedy this defect an invention has been applied by which the dial when illuminated at night throws out a beautiful transparent light admirably marking the position of the figures and hands, which being black or dark blue, or even strongly gilt, can also be distinctly seen by day, even as clearly as the long-approved copper dials painted black with gilt figures. THE HANDS