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 engine, 89. Valves of the electric light occupied so much has the Town Crier to say all you say; and working in comparatively pure air, and still unexplored fields which the.