Lavoisier-Laplace calorimeter. 19th-century artwork of the ice calorimeter developed in the period 1782 to 1784 by the French scientists Antoine Lavoisier (1743-1794) and Pierre-Simon Laplace (1749-1827). The central space (centre right) would contain burning oil (upper right), or an animal such as a guinea pig. The surrounding chamber would contain ice, the outer melted snow. The lid would be added and the amount of heat produced measured in terms of the volume of meltwater from the ice (lower left). This is Plate XI from 'Encyclopaedia Londinensis, or Universal Dictionary of Arts, Sciences, and Literature' (1801).