An isoperibol calorimeter is described. Its operation involves the dro
p of a sample from temperatures up to 1373 K into a metal block at 298
.15 K. By this method the enthalpy contents of the samples can be meas
ured. The calibration factor, obtained by electrical and drop calibrat
ions, had a reproducibility of +/-0.11%. The calorimeter was tested by
determining the enthalpy of silver; agreement with the data of Barin
was within a range of +1%.