An eye blister is a benign growth which can appear on the whites of the eyes or on the cornea itself. There are two main types of eye blister: pinguecula and pterygium.
Before x ray machines were invented, broken bones, tumors and the location of bullets were all diagnosed by physical examination and a doctor's best guess. Patients paid the price of these approaches. Then on November 8th of 1895, a German physics professor Wilhelm Conrad Roentgen made a remarkable discovery.
Becquerel used an apparatus similar to that displayed below to show that the radiation he discovered could not be x-rays. X-rays are neutral and cannot be bent in a magnetic field. The new radiation was bent by the magnetic field so that the radiation must be charged and different than x-rays.