Illustrated and descriptive catalogue of Roentgen X-ray apparatus and accessories : apparatus for the generation and application of high frequency currents. Apparatus for the therapeutic application of light energy.

  • Kny-Scheerer Company.
Date:
1905
Catalogue details

Licence: Public Domain Mark

Credit: Illustrated and descriptive catalogue of Roentgen X-ray apparatus and accessories : apparatus for the generation and application of high frequency currents. Apparatus for the therapeutic application of light energy. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    The Kny-Scheerer Company, New York. Telegraphic Address: EXHAY-NEW-YORK. X=RAY TUBES. Next to the inductor and the interrupter the Roentgen tube represents that part of the equipment upon which success almost entirely depends. It is sometimes possible to obtain satisfactory results from a poor X-Ray outfit if a good tube is used, but the best equipment is useless when a poor tube is connected with it. It must also be remembered that it requires large experience and care to select tubes suitable for the particular apparatus, and that the same X-Ray tube in the hands of different operators will not uniformly give the same results. A tube which proves eminently satisfactory in the hands of one may disappoint another and vice versa. According to permeability and thickness of the object to be skiagraphed, tubes of low, medium low, high and very high vacuum should be used. Tubes having a low vacuum are called soft, they are suitable for the bones of the hand, foot, ulna and elbow joint, and an exposure of from 5 to 30 seconds will give fine skiagraphs. Tubes having a medium low vacuum are called medium soft. They are used for the knee joint, shoulder, thigh, etc., a skiagraph requiring an exposure of from 25 to 60 seconds. Tubes having a high vacuum are called hard, and serve for skiagraphs of the chest, spine and pelvis; they require an exposure of from 40 to 60 seconds. Tubes having a very high vacuum are called very hard, the rarefaction of the intratubal air having been carried to the maximum point. The intensity of the rays ob- tained with these tubes is the greatest possible. The usual test object when selecting tubes is the human hand held in front of the Barium Platinum Cyanide screen. It includes bones together with soft parts of varying thickness. With a soft tube the bones of the hand will appear deep black and the soft parts dark. The bones of the wrist and the canals of the long bones are invisible. With a medium soft tube the bones of the hand appear greyish black and the soft parts very light. The canals of the bones are easily discernible, and the different wrist bones can be dis- tinguished. With hard tubes the bones are light grey in appearance, and the soft parts light and shadowy. The degree of vacuum in a tube is not permanent. At first a tube becomes softer when in use, because the particles of air which adhere to the tubal walls are detached from it by the warming influence of the current. After the tube has cooled it becomes harder again because the particles of platinum dissipated from the glowing anticathode, while cooling, meet molecules of air in the interior of the tube. The longer a tube is used the less will be its volume of air, so that finally there is too little intratubal air to permit the passing of a current. We suggest that the X-Ray tubes, when not in use be kept in a closet having a uni- form temperature, the shelves of which are padded with soft cloth. ALLOUR PRODUCTS xTrts*-ARE GUARANTEED AR OUR TRADE SL MARK ROR IDENTIFICATION == f1 '