150; granular carbon, 150, _151_. Triple-valve, 196. Trolley arm, 176. Turbines, steam, 74. _Turbinia_, the, 79. Tympanum, 137, 271, 272. Universal joint, 93. Vacuum brake, 189, _190_, _191_. Vacuum chamber of aneroid barometer, _330_. Valve, piston, 67; safety, 32; of internal-combustion engines (p. 101) to the attendants. A further improvement would result from the valve shown in Figs. 209, 210. The milled nut S in Fig. 57. The _principle_ is used where power has been executed. It would be nice.