Lee’s & Charlton’s Apparatus

It determines the elative conductivity of thin layers of materials, it consists of cylindrical brass slab of 11cm dia & 10.5mm thick. On this rest a 4.5cm deep brass hollow cylinder (Steam Chest) of the same dia with inlet & outlet tubes for stem. A hole for thermometer is drilled radially in each, and the cylindrical brass slab is fitted with eyelets to enable  it to be suspended by three strings from stout annular ring. The ring is held on a heavy retort stand complete as above with accessories but without thermometer.