[Larger plate.]

[1673]. Equilibrium plug or cylindrical valve, double ported.

[1674]. Another form of self-lifting valve. See [No. 1671] for description.

[1675]. Compound flap valve.

[1676]. Indiarubber pump valve.

[1677]. Venetian shutter or compound butterfly valve.

[1678]. Bye pass used to allow a small flow when the main valve is shut off. Used also to equalise pressure on both sides of a large valve to enable it to open easily.

[1679]. Bell and hopper, or cup and cone; used for blast furnaces, coke ovens, and gas generators.

[1680]. Cup valve and suspended weight.

[1681]. Four-way valve for hot water pipes, &c.