Shortly after J.J. Thompson discovered the electron in 1887, he was able to measure the specific charge of the electron, the ratio of the charge of the electron to its mass, . In this lab, you will perform an improved version of Thompson's experiment and determine the ratio of the charge of an electron to its mass, , through the use of Helmholtz coils. These coils are named for Hermann von Helmholtz who discovered how to use the electromagnetic coils to produce a highly uniform magnetic field. In 1909, Robert Millikan's Oil Drop experiment showing that charge is quantized, made it possible to determine the charge of an electron, , independently. Through both experiments, the mass of an electron, an extremely small quantity, can be obtained