Today is the birthday of Guillaume Amontons, born in 1663, he invented a new hygrometer in 1687, and improved Galileo’s thermometer in 1695, He should be more famous for Amonton’s Law. Everyone talks about Boyle’s Law and Charles’ Law but fail to mention Amonton’s Law, He said that the pressure of a gas increases with increased temperature. He also said in 1702 that if the temperature dropped enough, there would be no pressure, thus an absolute zero. This concept was made known by Lord Kelvin in 1848.
Today is also the birthday of Michel Chevreul, born in 1786, he was a chemist who discovered margaric acid and designed an early form of soap made from animal fat and salt, he died in 1889 at the age of 102.
Hermann von Helmholtz, born in 1894, he discovered the principle of conservation of energy while working on muscle metabolism, he invented the opthalmoscope for observation of the inside of the eye, he wrote several theorems on the vortex dynamics of fluids, he wrote the Helmholtz equation for electromagnetism, and did many other things, he died in 1894 at age 73.
Bernard Lovell, born in 1913, was a radio astronomer, he died in 2012 at age 98.
David Politzer, born in 1949 received the Nobel Prize in Physics for the discovery of asymptotic freedom in quantum chromodynamics.