Roentgen's X-ray machine. Drawing of the X-ray machine used by German physicist Wilhelm Roentgen to produce images of the hand. The generator (B) supplied a high voltage to the cathode ray tube (Crookes tube) at upper right (T). This tube produced X-rays which left an image of the hand on a covered, photographic plate (C). Roentgen had discovered X-rays on 8 November 1895. In the following weeks he made images of many objects including, after a 15 minute exposure time, his wife's hand. This, the first-ever X-ray of part of a human, showed the outline, bones and metal jewellery of the hand. Medical radiography is now widespread. Image of an 1895 machine.