Callender and Barnes Apparatus ABRON  Horizontal Borosilicate glass tube open at both ends with inside heating element coil Nichrome wire. All on a polished wooden base with constant level tank, stand 2 thermometer-695-A    Complete on base  optional  AP-695-B         Power supply 0-12 volts

         AP-695-K    Callender & Barns Apparatus setup Complete set ( APP-2301-047 ) with power supply, 2 thermometers Galvanometer, Voltmeter, Rubber tube 2 meter , Pinch clip, Stop watch Digital