An Improved Version of the Classical Bodenstein Valve In 1930, Bodenstein' described a. greaseless all-glass valve, consisting of a. glass bellows, s. capillary, and a glass rod. The end of the glass rod was carefully ground to a hemisphere, which fitted into a cornsponding socket a t the end of the c a p i l l a ~ . It proved to be rather difficult to grind the two counter parts of the valve in such s w a y to prevent completely any leakage across the closed system. This problem may be easily solved by using commercially mailable ball-and-socket joints as the valve coniponents inside the elass bellows. The fieure shows rt drawine of the imoroved nt,den.\win valve. The availability of ball-nnd-sovket joints i r l dilfcreht . d m makes it po&l,k to nlnnulwture such g1a;i.i bell~ws vnlves in nun). different $ires, depending on the intended use.
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BODENSTEIN, M., 2.Physikal. Chem., B7, 388 (1930); VAUQHAN, W. E., Rev. Sci. Inatr., 16, 254 (1945).
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Journol of Chemical Education
