In many cases the author has omitted stating, in taking sciagraphs, that the films were protected from ordinary light by opaque material. This, as a matter of course, has always been understood. Battelli also had the films wrapped in material opaque to ordinary light. Experimenters should, if possible, always employ aluminum for this purpose, because the author has always noticed that black paper or cloth permits a great deal of light to come through, even when in double thickness.
Prof. Sylvanus P. Thompson (The Electr., Lon., June 26, ’96) located a wire in a focus tube in the path of the rays between the platinum reflector and the wall of the tube. Not only was there a sciagraph of this wire produced in the sciascope, but also the Crookesian shadow of the wire on the wall of the bulb. For this experiment the exhaustion must be quite high. “At no state of exhaustion did the platinum reflector convert all the internal cathode rays into X-rays.” Both shadows were cast by the platinum reflector as the origin. More or less of the rays between the reflector and the glass were sensitive to a magnet.
Bleyer’s Experiment. [§ 165].
Combined camera and sciascope at the left: and showing induction coil and discharge-tube at the right.
165. Bleyer’s Experiment. Combined Camera and Sciascope. Elect. Eng., July 1, ’96; Royal Acad. Med. & Sur., of Naples, Italy.—As early as April 7, J. Mount Bleyer, M.D., of Naples, constructed and used the apparatus shown in the adjacent cut, p. [169]. The picture is self-explanatory. Attached to an ordinary camera is a flaring sciascope, for receiving the temporary sciagraph of the hand, for example. The X-rays are converted into luminous rays by the fluorescent screen, and, therefore, the camera will serve to take a picture by means of the luminous rays from the sciagraph of the hand. The cut represents also an induction coil and a discharge tube. Soon afterwards, it was reported by an English paper that Dr. Levy, of Berlin, and others of England, had also made similar tests with success. In order to illustrate the applicability of the combination, Dr. Bleyer took many sciagraphs with the camera. He calls it the photofluoroscope, which, however, will probably not meet with favor for the name does not suggest the nature of the instrument. When two radically different devices are combined into one, it is difficult to formulate an acceptable single word, and, therefore, the instrument will probably always be called by some of the following terms: A camera with sciascopic adjustment, or combined sciascope and camera, or corresponding combinations with the word fluoroscope.
From the time that Roentgen’s discovery was announced, scientists throughout the world have made careful experiments, up to date, in all possible directions, and the time has now come when the number of experiments is rapidly decreasing, only one or two being noted now and then in the scientific press, and consisting mostly in repetition, with occasionally a slight departure, involving a radically new subordinate discovery; but in view of the great number of scientists, and of their high standing as careful experimenters, and because also of their desire to be correct in their inferences, there might seem to be little else to be investigated. Time only will tell. Before passing to the final chapters relating to other matters, a few more experiments are related in the briefest manner.
166. Prof. Sylvanus P. Thompson confirmed non-polarization, (Phil. So., June 12, ’96, and The Electr., Lon., June 26, ’96.)
Dr. John Macintyre (Nature, June 24, ’96) carried on a long series of experiments with tourmaline, and also arrived at the conclusion that polarization of X-rays is practically impossible, [§ 97], at end.
From Sciagraph by Prof. Goodspeed, showing Curvature of the Radius, due to Arrested Development of the Ulna at its Distal Epiphysis. One Bone shown through another.