960. Sievert, P. T. Jan. 17. Blowing; drawing; moulding shaping.-Relates to the invention described in Specification No. 18,917, A.D. 1904. In order that the thickness of the hollow body produced may be uniform, the temperature of the middle of the cake of glass is arranged to be somewhat lower than that of the sides at the time of blowing. To accomplish this, the glass is cast in a mould a, Fig. 2, with a central raised part b, which causes the glass to be thinner and hence to cool quicker at the centre than at the sides. In the subsequent re-heating, this difference of temperature is to a great extent maintained. The same result may be effected by a suitable distribution of water cooling-coils in the base of the mould a. The form of mould shown in Fig. 4 is suitable for the production of baths, pipes, &c. by this process.