An instrument is described which can be used to obtain a continuous
record of the weight of a fire during laboratory experiments.
Essentially the device consists of a central weighing platform mounted
on four beams which carry electrical resistance strain gauges arranged
in a temperature compensated bridge circuit. The design and
construction of the device is described and calibration curves are given
for three ranges of fire weight. An example is given of the convective
heat output characteristic of a fire obtained with the instrument.
