This apparatus is used for determination of mechanical equivalent of heat using this apparatus. Consists of a horizontal corning glass tube of 360mm long open at both ends. The heating element is a coil about 40cm long of Ni-chrome wire and is wound spirally inside the axis of the glass tube. The element is easily detachable and is encased in a wooden case lined with felt and provided with a hinged cover. The leads are carried to terminals fixed on the base for the electrical supply. The horizontal tube is connected either by rubber tube or rubber cork to the inlet and the outlet system, each having a short vertical extension to accommodate a thermometer. Complete apparatus mounted on a polished wooden base board. Supplied with constant level tank fitted on stand but without thermometer & Transformer.