James Chadwick
James Chadwick was born on October 20, 1891. He enrolled into Victoria University in Manchester and studied physics. In 1911 Chadwick graduated out of the Honors School in physics. Chadwick knew Niels Bohr and Hans Geiger and occasionally worked with them in the department of physics. Chadwick also received his masters in 1913. Chadwick worked for many years in physics and worked with the atom and the charges of the subatomic particles and the nucleus. Eventually after finding an unnamed particle and discovering it's atomic mass Chadwick had discovered the neutron! This is why even though Hydrogen has 1 proton and Helium has 2 the ratio of Helium to Hydrogen is 4:1 because the neutrons in Helium. Chadwick was awarded a Nobel Prize in physics in 1935 after his discovery. James Chadwick died on July 24, 1974.
Robert Millikan
Robert Millikan was born March 22, 1868 in Morrison, Illinois. Millikan was an American Physicist who was awarded a Nobel Prize for Physics in 1923 for his studies and measurement of elementary electronic charge. Between the years 1908-1917 Millikan worked and measured the charges of subatomic particles, specifically the electron. Through his work and studies Millikan used a device in an experiment that used an atomizer from a spray bottle to spray liquid droplets into a a sample container.Millikan observed some of this experiment within the container with a microscope. Eventually, by studying each droplet Millikan was able to use the charges from the droplets to find that it is always a multiple of 1.59x 10^-9. Millikan also discovered the charge and mass of the electron is mass= 9.1x10^-28g . Millikan used this and other information to conclude the mass of an electron is at least 1000 times lighter than the lightest atom. Millikan died December 19, 1953.