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12.11.2010

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X-RAY PHOTOGRAPHY
X-ray photography was one of the most important dis- coveries of the 19th century. Developed in November 1895 by German scientist Willhelm Conrad Röntgen (1845–1923), the x-ray thus straddles the cusp between two centuries. The phenomenon captured the public’s imagination to an extent not experienced; its fascination was not to be eclipsed until the hydrogen bomb in 1945. The aesthetic and theoretical ramifications of x-rays also proved fertile ground for artists seeking new ways to picture inner realities. Röntgen won the first Nobel Prize in Physics in 1901 for his breakthrough, yet declined to seek a patent and remained modest about his remarkable discovery for the rest of his life. Interestingly, Röntgen disliked being photographed, therefore few images of him exist.
Röntgen, like many other researchers of his time, was interested in the nature of cathode rays. To ac- complish his light experiments, he used vacuum glass tubes, commonly known as Crookes tubes after William Crookes, a British scientist who perfected them in the 1870s. Working in the Physical Institute laboratories of the University of Wurzburg, Röntgen studied emissions produced from an electrical current passed between the cathode (negative) and anode (positive) terminals. The cathode rays normally caused the walls of tube or other internal objects to glow, but did not seem to be able to penetrate the glass. Röntgen was astonished when his cardboard shrouded tube caused a barium platinocyanide screen across the room to fluoresce. Placing various objects between the tube and screen, he saw the bones of his hand through his flesh, which he subsequently captured on a photographic plate. What followed was seven straight weeks of intense experimentation. He remarked to a friend, “I have discovered something interesting, but I do not know whether or not my ob- servations are correct.”
On December 28 1895, Röntgen gave a preliminary report to the Physical-Medical society of Wurzburg, and by New Year’s Day he sent copies of his report to colleagues across Europe. Newspapers and magazine quickly picked up the story and by January, the whole world was caught up in x-ray fever. Other non-existent rays were posited—including N-rays, black rays, and Becquerel Rays (later found to be the alpha, beta, and gamma rays produced by radioactive materials). Every imaginable substance, including animals and objects, were exposed. Eager for news of each new photographed organ, cartoonists and poets lauded the humorous new possibilities of seeing people’s thoughts and peering through underwear. By 1896, over 60 articles had been featured in the popular press as well as the first angiography, cinematic x-ray, and military radiology performed.
The first generally-accepted x-ray photograph is that of Mrs. Röntgen’s ringed hand from December 22, 1895. (After learning of the discovery, A.W. Goodspeed and William Jennings recreated one they had made by accident in 1890.) X-rays were seen as extension of the photographer’s craft and were included in many manuals and journals. After Thomas Edison’s invention of the fluoroscope in 1896 (a kind of hooded camera fitted with a screen), many x-rays were performed as demonstrations. People lined up at department stores, high schools, and other public venues to get “bone portraits.” Dubbed “shadow photographs,” X-rays soon after needed no camera, a capacity shared with some of the earliest forms of photography, and no film. Still, the evidentiary nature of a photograph proved irresistible, especially to photographers, scientists, and the press. Eadweard Muybridge made stop action photographs and films of frog’s legs in motion in 1896. Edison even claimed that the rays would eventually show the activity of the human brain.
As x-rays are radiation, they can both diagnose and cure. Enthusiasts, not having a precedent, exposed them- selves regularly to test strength and perform demonstra- tions. Reddening of the nose and hands of practitioners was common. The early decades of the 20th century saw the death of many early pioneers due to numerous amputations and burns resulting from overexposure. It was not until the death of Edison’s assistant in 1904 that the spotless record of the rays began to wear thin. The novelty and pure aesthetics of the rays gave way to medical applications—both legitimate and illegiti- mate. Medical schools added x-rays to their curricula; likewise, correspondence courses offered programs for photographers and electricians to gain training in “Röntgenology.” “Do-it-yourself” kits were even sold in popular magazines.
Röntgen initially described x-rays as “longitudinal vibrations in the ether”. The ether was a commonly held scientific hypothesis that a mysterious substance occupied the air and was the media through which waves and a whole host of other as yet inexplicable phenom- ena moved. At the turn of the last century, science and occultism occupied a much closer range than they do today and x-rays were thought by many to give credence to extra-sensory perception and psychic ability. If such non-perceptible spectacles could be captured on a pho- tographic plate, it was argued, so too could thoughts, auras, ghosts, and even the human soul. Philosophically, the discovery of x-rays caused a scientific sea change. No longer did the senses seem an adequate platform for analysis; scientific positivism was at a standstill.
Furthermore, these rays could also kill as well as cure, presenting a medical and moral conundrum.
It was not until the 20th century that x-rays were confirmed to be a part of the electromagnetic spectrum. Röntgen had covered his tube to keep the fluorescent effects contained; yet he found that the new rays could not be reflected, polarized, or refracted. It was later proved that x-rays have shorter wavelengths than visible light (around one billionth of a meter) and are related to radioactivity (discovered in 1896 and later studied by Marie and Pierre Curie). A trained glass blower, C.H.F. Muller was the first to construct commercially viable x-ray tubes and was later granted a patent in 1899. His firm expanded until another company took over in 1927, eventually setting the foundation for the new and improved x-ray apparatus we know today.

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