A man seated in a barrel with his head under a glass canopy; he breathes and his pulse is taken; Lavoisier dictates to his wife who is writing a report. Drawing attributed to M.A.P. Lavoisier, ca. 1790.

The following identifications are from Beretta, loc. cit. The seated man who is the subject of the experiment is Armand Séguin, who had assisted Lavoisier in his experiments since 1785. The unbewigged man taking his pulse may be the Scotsman Hugh Gillan. On the left Lavoisier makes a gesture towards his wife, who is seated at a table with a pen in her hand. On the right a man seems to collect air from below the canopy: he may be Jean-Henri Hassenfratz who participated in some of the experiments on respiration by Lavoisier and Séguin.The purpose of the experiments was to distinguish the effects of respiration, transpiration, pulmonary transpiration and cutaneous transpiration