Today, 240 years ago, on January 12, 1785 (December 2, 1784) the French chemist and physicist Dillon was born. On January 12, 1785, the French chemist and physicist Dillon was born. Dillon discovered the nitrogen chloride at the age of 26, and two years later produced the intense trichloride nitrogen. At the age of 34, Dillon and Perth discovered that most of the solid solids are almost equal to the accumulation of thermal capacity and atomic mass, this is the famous Dillon-Percy law, which has played a very important role in the history of chemical development.