213,296. Gibson, R. K. Dec. 22,1922. Gas meters.-In a gasmeter of the type wherein a seamless annular diaphragm of leather &c. is attached by its outer edge to a ring fixed on the partition of the meter and by its inner edge to the edge of a sheet-metal disc, the whole forming a frusto-conical chamber, the diaphragm is shaped by a former-block made in sections A<4>. The sections are mounted on a frame A<5> formed with pockets A<6> for the reception of projections A' pro. vided on the sections, and are retained in position by rims A, B clamped thereon by means of plates A<1>, A<2> carried by a screwed central spindle A' and nut B'. The diaphragm is tied to the rim B, stretched over the former-block, and then tied to the rim A, after which the'block is removed by first withdrawing the frame A<5> and then the sections A<4>. The rim A is soldered to the meter partition and the chamber closed by a disc which is soldered into the rim B.