In science, Joseph Black (1728-1799) was a Scottish physicist and chemist notable for his scientific investigations into the nature of heat, for being a mentor and financier to Scottish mechanical engineer James Watt, and for his discovery of the phenomenon of “latent heat”, calculations of which were later used by French chemist Antoine Lavoisier and Pierre Laplace in their 1782 invention the “ice calorimeter”, which was used to determine the heat evolved in various chemical reactions. Black’s mentor was Scottish physician and chemist William Cullen, notable for being the first, in 1757, to make diagrams of affinity reactions in chemistry. Through this interaction, both Cullen and Black arrived at the view that heat may have a significant effect on affinities. [1]