They are invisible rays transmitted through the air in a manner similar to light. They are produced by passing unidirectional electric current of from twenty to one hundred thousand volts pressure through a specially constructed high vacuum tube, within which rays radiating from the surface of a concave cathode (the negative electrode of a galvanic battery), are focused upon and bombard a target of refractory material such as tungsten, iridium, platinum, from which focus spot the X-rays radiate in all directions.
They are used in medicine and surgery, to photograph the skeleton and all the internal organs of the human body, as an aid in diagnosis; also to destroy diseased tissue without the aid of surgery. Cancers and tumors of certain kinds and a number of skin diseases are said to be made to disappear by their use. When the apparatus is used, the subject is placed on a long table and the X-ray tube, in its lead glass shield container, is brought over the part of the body to which the rays are to be applied.
The most up-to-date apparatus consists of a high-tension transformer and rectifier, driven by a rotary converter, which derives power from direct-current electric service and delivers alternating current to the high-tension transformer.
Modern X-Ray Apparatus
How did the Term “Yankee” Originate?
Although some people maintain that the word “Yankee” originated with the way white men interpreted the Indians’ name for the early settlers, most of those who have wondered about it have decided that it came to be used as a nickname for persons born in the United States, because of a farmer, named Jonathan Hastings and living in Cambridge, Massachusetts, in the eighteenth century, using it to describe some good, home-made cider of his making, as “Yankee cider.” The word was taken up by the students of Harvard University, and gradually spread throughout the whole country.