The calorimetric bomb, prepared as described in DIN 51900 Part 1, August 1977 edition, Section 10, is placed in the calorimeter vessel which has been filled with water and placed inside an isothermal water jacket. The fuel sample is ignited, the curve of the temperature rise of the calorimeter water which occurs is observed and recorded. From this, the corrected temperature rise is calculated on the basis of Newton's Law of cooling and the gross calorific value of the sample determined, taking into account the effective heat capacity of the calorimeter system (see Notes).