Static screw elevator

Bates, L. (October 2005) The static screw elevator. Proceedings of the 8th International Conference on Bulk Materials Storage, Handling and Transportation, University of WoUangong. 

Application of the ebulliometric method at elevated pressures has already been discussed. The method has been used only occasionally, and most vapour-pressure measurements in the range now considered have been made by the static method in apparatus which is, in principle, the same as that used by Andrews for his work on the isotherms of carbon dioxide, and subsequently developed by Hannay and by Ramsay and Young. The sample is confined over mercury in a thick-walled glass tube sealed at its upper end, and the tube is attached to a steel U-tube containing mercury the pressure is transmitted through the mercury to the pressure gauge and a piston on a screw allows the level of the mercury, and hence the volume occupied by the sample, to be adjusted. The experimental tube is heated by means of a vapour jacket. (Alternatively, the glass tube itself may be bent into the form of a U, often then known as a Cailletet tube, and the apparatus is heated by immersion in a normal thermostat bath. )... 

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