effects of the rays in air or in a sec- shadowy pictures they produce ond glass tube into which he directed bones in a hand, a wire wrapped them around a bobbin, weights in a box, Roentgen, a meticulous and ob- a compass card and needle hidden rvant experimenter, made the away in a metal case, the inhomo- obvious tests on the new X rays: geneity of a metal. The ability of the Were they propagated in straight new rays to produce photographs lines? Were they refracted? Were they gave them great popular appeal and reflected? Were they distinct from brought Roentgen fame. Many arti cathode rays? What were they? Like cles appeared in photography jour- Heinrich Rudolf Hertz. 1857-1894 the cathode rays, they moved in nals, and The New - York Times in (Courtesy of Deutsches Museum and straight lines. Roentgen was unable dexed the new discovery under AIP Emilio Segre Visual Archives) to refract them with water and car- photography. Since the rays expose bon bisulphide in mica prisms. Nor photographic plate the public as- could he concentrate the rays with sumed they were some form of light ebonite or glass lenses With ebonite The physicist Roentgen concurred and aluminum prisms he noted the Accepting Lenard's claim that cath- possibility of refracted rays on a pho- ode rays were vibrations of the ether, tographic plate but could not observe Roentgen compared the new rays to this effect on a fluorescent screen. them and forwarded the opinion that Testing further, he found that X rays the two were ethereal, although dif- O Rontgen, then the news is true could pass freely through thick lay- ferent from visible, infra-red and And not a trick fide rumour ers of finely powdered rock salt, ultra-violet light in that they did not That bids us each beware of you. electrolytic salt powder, and zinc reflect or refract. He suggested that And of your grim and graveyard humour dust, unlike visible light which, cathode rays and X rays were longi We do not want like Dr: Swift. because of refraction and reflection, tudinal vibrations of the ether rather To take our fesh offand is hardly passed at all. He concluded than transverse ones ones or that X rays were not susceptible to Now that their existence was And joint for you to poke e your nose n egular refraction or reflection. established, it was easy enough to Roentgen found that the X rays experiment with the new X rays. We only crave to contemplate Each others usual full-dress photo originate from the bright fluores- Roentgen himself published only Your worse than altogether"state cence on the tube where the cathode three papers on the subject, but oth- Ofportraiture we bar in toto/ rays strike the glass and spread out. ers jumped quickly into the field The point of origin of the X rays And not just physicists. Thomas The fondest swain would scarcely prize moves as the cathode rays are moved Edison used modified incandescent A picture of his lady 's framework; by a magnetic field, but the X rays light bulbs to produce the new rays To gaze on this with yearning eyes Would probably be voted tame work/ themselves are insensitive to the He boasted to reporters that any magnet Roentgen concluded that one could make photographs of No, keep them for your epita they are distinct from cathode rays, skeleton hands; that was mere child,s these tombstone-souvenirs unpleasant, since Lenard's work had shown that play. Within a month of Roentgen Orgo away and photograph cathode rays passing through the announcement doctors were using Mahatmas, spooks, and Mrs. B-s-nt/ tube maintained their direction the X rays to locate bullets in human but were susceptible to magnetic flesh and photograph broken bones -Punch, January 25, 1896 deflection Dr Henry W. Cattell, Demonstrator Roentgen justified calling the new of Morbid Anatomy at the Univer phenomena rays because of the sity of Pennsylvania, confirmed their 14 SUMMER 199514 SUMMER 1995 effects of the rays in air or in a sec￾ond glass tube into which he directed them. Roentgen, a meticulous and ob￾servant experimenter, made the obvious tests on the new X rays: Were they propagated in straight lines? Were they refracted? Were they reflected? Were they distinct from cathode rays? What were they? Like the cathode rays, they moved in straight lines. Roentgen was unable to refract them with water and car￾bon bisulphide in mica prisms. Nor could he concentrate the rays with ebonite or glass lenses. With ebonite and aluminum prisms he noted the possibility of refracted rays on a pho￾tographic plate but could not observe this effect on a fluorescent screen. Testing further, he found that X rays could pass freely through thick lay￾ers of finely powdered rock salt, electrolytic salt powder, and zinc dust, unlike visible light which, because of refraction and reflection, is hardly passed at all. He concluded that X rays were not susceptible to regular refraction or reflection. Roentgen found that the X rays originate from the bright fluores￾cence on the tube where the cathode rays strike the glass and spread out. The point of origin of the X rays moves as the cathode rays are moved by a magnetic field, but the X rays themselves are insensitive to the magnet. Roentgen concluded that they are distinct from cathode rays, since Lenard’s work had shown that cathode rays passing through the tube maintained their direction but were susceptible to magnetic deflection. Roentgen justified calling the new phenomena rays because of the O, Röntgen, then the news is true, And not a trick of idle rumour, That bids us each beware of you, And of your grim and graveyard humour. We do not want, like Dr. Swift, To take our flesh off and to pose in Our bones, or show each little rift And joint for you to poke your nose in. We only crave to contemplate Each other’s usual full-dress photo; Your worse than “altogether” state Of portraiture we bar in toto! The fondest swain would scarcely prize A picture of his lady’s framework; To gaze on this with yearning eyes Would probably be voted tame work! No, keep them for your epitaph, these tombstone-souvenirs unpleasant; Or go away and photograph Mahatmas, spooks, and Mrs. B-s-nt! —Punch, January 25, 1896 shadowy pictures they produce: bones in a hand, a wire wrapped around a bobbin, weights in a box, a compass card and needle hidden away in a metal case, the inhomo￾geneity of a metal. The ability of the new rays to produce photographs gave them great popular appeal and brought Roentgen fame. Many arti￾cles appeared in photography jour￾nals, and The New-York Times in￾dexed the new discovery under photography. Since the rays exposed photographic plate, the public as￾sumed they were some form of light. The physicist Roentgen concurred. Accepting Lenard’s claim that cath￾ode rays were vibrations of the ether, Roentgen compared the new rays to them and forwarded the opinion that the two were ethereal, although dif￾ferent from visible, infra-red and ultra-violet light in that they did not reflect or refract. He suggested that cathode rays and X rays were longi￾tudinal vibrations of the ether rather than transverse ones. Now that their existence was established, it was easy enough to experiment with the new X rays. Roentgen himself published only three papers on the subject, but oth￾ers jumped quickly into the field. And not just physicists. Thomas Edison used modified incandescent light bulbs to produce the new rays. He boasted to reporters that any￾one could make photographs of skeleton hands; that was mere child’s play. Within a month of Roentgen’s announcement doctors were using the X rays to locate bullets in human flesh and photograph broken bones. Dr. Henry W. Cattell, Demonstrator of Morbid Anatomy at the Univer￾sity of Pennsylvania, confirmed their Heinrich Rudolf Hertz, 1857–1894. (Courtesy of Deutsches Museum and AIP Emilio Segrè Visual Archives)