Injurious Effects of the Roentgen Rays Page 4

qualify as more or less dangerous any exposure to their action. Notwithstanding these objections, the use of the x-rays in surgical diagnosis is destined to become general. Cases are on record (1) in which even the courts are required to accept the skiagraph as corroberative evidence of expert testimony.

The theories adduced to account for the injuries resulting from the application of the x-rays, inducing the "x-ray burn," have not as yet afforded either a remedy for the lesion or a way to avoid it.

The following series of experiments* have been conducted by the writer during the past six months in the study of the problem.

The x-rays were produced by means of the static electric current from a Wimshurst or influence machine having eight circular plates of blown glass each twenty-eight inches in diameter, revolve at a high rate of speed between an equal number of stationary plates. The power was supplied by an one-half horsepower motor of the Crocker-Wheeler type connected with the current used for lighting the building. The apparatus is supplied with Leyden jars, in circuit or not, accessory spark gaps, and all adjustments for perfect regulation to secure the best results from the vacuum tubes. The tubes used were fourteen inches in length, having each a bulb three and one-half inches in diameter, enclosing aluminum cathodes and platinum anticathodes, also provided with an auxiliary potash tube to be connected in circuit by a shunt, so as to reduce the vacuum when it became too high. In this manner the tubes could be so adjusted to the potential of the current as to produce x-rays of the greatest brilliancy and penetration, and maintain their uniform production for an indefinite period without danger of breakage by perforation.

Two guinea pigs kept upon the same conditions of food, etc., were used - one for the experiments and one for the purpose of normal comparisons. Exposed a pig to the x-rays at a distance of three inches from the tube for a period of twenty minutes in order to accustom her to the slight annoyances of noise, etc., incident to the following experiments.

The only effect of the exposure was a slight drowsiness, which gradually passed away. No further effects of the exposure became apparent during the following week. Accordingly the pig was again exposed to a low vacuum tube giving x-rays of a poor quality, at a distance of one inch from the surface of the tube, for ten minutes; and again to a high vacuum tube emitting intensely brilliant x-rays, at the same distance, for a period of two hours. During this time the pig was confined in a pasteboard box perforated by a window one and one-half inches square, directly opposite the pig's right lateral thoracic wall. She remained quiet in her box except at intervals she would shift her position as if uncomfortable, but would immediately return to her former position. Three or four times she appeared to act as if something annoyed her belly and endeavored to reach the spot with her nose, but after some slight effort subsided into quiet.

During this time the table on which the pig rested became strongly electrified, and no doubt the pig was electrified as well.

She acted entirely normal, and no cutaneous or other effects were noticeable for one week after the exposure.

The fur was then clipped from a region one inch square, over the right lateral thoracic wall, which had been previously exposed, and again submitted to action of rays of greatest brilliancy for a

* The experiments mentioned in this paper were conducted in the photographic and x-ray laboratories of the Department of Pathology in the College of Physicians and Surgeons. Medical department of Columbia College in the City of New York, under the guidance of Dr. Edward M. Leaming, F.R. P.S. instructor in photography, photomicography and skiagraphy in the above institution. The microscopic data here presented were supplied by the courtesy of Dr. Frederick S. Ward, assistant in Normal Histology in the Department of Pathology.