Melting Point Apparatus PSAW the apparatus is useful in determination of melting point (upto 300oC) of any substance in small quantity. It consists of an aluminium block which accepts three capillary tubes and a mercury thermometer. The block is heated by two elements clamped to the sides. The built in lamp provides uniform and shadowless illumination of sample tube which are viewed through magnifying lens against either a dark or bright ground selected by rotation of knob at the rear of apparatus.