In the celsius scale of temperature, the ice-point is taken as taken as the lower fixed point (0 deg C ) and the steam-point is taken as the upper fixed point (100 deg C). The interval between the ice point and steam point is divided into 100 equal divisions. Thus, the unit division on this scale is 1degC. This scale was earlier called the centigrade scale. 1 deg C = 9/5 deg F.