High-resolution, full color images available online
Search, browse, read, and print yearbook pages
View college, high school, and military yearbooks
Browse our digital annual library spanning centuries
Support the schools in our program by subscribing
Privacy, as we do not track users or sell information
Page 9 text:
“
1650 Otto Von Guericke invented the first air pump, later used to produce a vacuum in a Crookes ' Tube. 1831 Michael Faraday discovered the process of electromagnetic induction by the relative motion of a magnet and a conducting wire. Without the application of this profoundly important principle to the induction coil and high-voltage electric currents, the present use of X-rays would be impossible. 1831-1856 Period of transition in early design of static machines, induction coils and transformers for producing high voltage. 1837 Michael Faraday experimented with rarefied gases producing luminous effects created by electric discharges through these media. 18 51 Ruhmkorff produced the first induction coil, later used for energizing the X-ray tube. 18 57 Heinrich Geissler, a German scientist of the City of Bonn, constructed the first vacuum tube and noticed that an electrical discharge passed through a vacuum tube produced a glowing. This was termed fluorescence. 1865 Herman Sprengel invented the mercury air pump the use of which resulted in the production of high rarefactions with comparative rapidity. 1874 Original Crookes ' Tube demonstrated by Sir William Crookes. 187 5 Sir William Crookes, an eminent English scientist, exhausted tubes to approximately one-millionth of an atmosphere pressure, the degree of vacuum necessary for the production of the X-ray. 1873 Sir William Crookes discovered that high voltage electric current, in its passage through a highly evacuated tube, was being carried by a stream of radiant particles, originating at the negative terminal. These were later called cathode rays. 1888 Professor Heinrich Hertz succeeded in proving a mathematical proposition stated by Maxwell in 1866: that an electrical disturbance should develop waves in the ether. Lenard, a pupil of Hertz, demonstrated the effect of the cathode rays on crystals of barium platinocyanide and sensitive photographic plate. 1895 November 8. Roentgen ' s observation was made on a Friday evening, while he was working alone in his laboratory. When the room was darkened and the current turned on. Roentgen noted a fluorescence emitting from a barium platinocyanide screen on the wall some distance from the Crookes ' Tube. While walking toward the screen, Roentgen crossed the path of the rays and noticed the shadow of his hand appearing on the coated side of the screen. The fluorescence on the s;reen was not of prime importance — it was the fluores- cence of the screen in the shadow which attracted Roentgen ' s attention, and his following up this first observation yielded the discovery of the X-ray. First demonstrated roentgenogram: weights in closed wooden box. 1896 January. Dr. Otto Walkhoff, a dentist of Braunschweig, Germany, made the first dental radiograph; exposure time was 2 5 minutes. February. The first X-ray picture of the teeth was exhibited by Professor Koenig to the Society of Physics at Frankfurt, Germany. April. Dr. William James Morton, of New York, made the first dental radiograph in the United States, and was followed soon by Drs. Van Woert, Ottolengui, and C. Edmund Kells. June. X-rays first mentioned in American dental literature. Kirk, Edward C; Editorial {Dental Cosmos) and Morton, William J.; X-ray and Its Application to Dentistry. (Dental Cosmos). August. Dr. C. Edmund Kells, of New Orleans, gave the first dental X-ray Clinic ever held in the United States, at Asheville, N. C. After a period of constant devotion to the development of radiodontia Dr. Kells died a martyr to the cause. Professor Jackson of Kings College, London, invented the first single-focus tube for X-ray work. 1896-1898 Caustic potash bulb used to regulate amount of current. Concave aluminum cathode used in some of the first tubes. 1896-1913 Period of transition in the design and manufacture of gas X-ray tubes, rectifiers, rotary converters and spark gaps, advancing from the Telsa transformer, high-frequency type of machine, and induction coil type to the more modern oil immersed transformer type which became more popular with the advent of the Coolidge Tube. 1897 June. Dr. Van Woert was the first person in America to use a filin intraorally. ' 1899 Ruhmkorff Coil built especially for Roentgen-ray work. Thomson and Tesla experimented with the high-frequency alternating current and found that with a very high oscillation the current would excite the single-focus tube and not produce the undesirable heating effects. Ramney-Wimshurt-Holtz Static Electric Machine: current source for excitation of Crookes ' Tube. Double-focus vacuum tubes replaced the single-focus type to compensate for the change of current, i.e., D.C. to A.C. (Continued on next page)
”
Page 10 text:
“
Chronology of the X-Ray (Cunfinncd from preceding page) May 10. Dr. Kells made the first use of a diagnostic wire in root-canal therapy. First automatic regulation tube. Crookes ' Tube with hollow platinum target devised. Platinum reflector added for use with heavy currents. Platinum circular target first used on Crookes ' Tube. 1907 Professor A. Cieszynski of Lwow, Poland, described an angle meter for measuring the chief ray in the per- pendicular plane. (Described by Dr. Raper in 1924). First rotary converter installed in Jefferson Hospital in Philadelphia. 1908 First application of ductile tungsten as a substitute for platinum in the target of the X-ray for controlling milliamperage of current by Dr. Coolidge of the General Electric Research Laboratory. Original dental films packet produced by Eastman Company. 1910 Formal education in Radiodontics was given in eight Dental Schools. One school had demonstrations by staff instructors. 1911 Dr. Howard Raper published the first series of articles on X-ray in Dental Itetm of Interest. 1912 Dr. Weston Price first suggested the use of a triple-coated film. 1913 First commercial handwrapped periapical dental X-ray film packet. 1913 Dr. W. D. Coolidge developed the hot-cathode X-ray tube, a new type of high-vacuum tube with a hot tungsten filament for the source of electrons. Dr. Cieszynski published the first handbook on roentgenology, in which he outlined both the intra-oral and the extra-oral techniques. (Copy of book sent to Dr. Raper). Dr. Howard Raper wrote the first textbook on roentgenology, established the first full-time course in a dental college and coined the word radiodontia. The Dental Education Council recommended 16 hours for Radiodontics. Mention was made of clinical as well as of theoretical study. Piffard Tube and Automatic Regulator produced. Occlusal, or bite, film first made. Development of the radiator-type of Coolidge Tube. Cossor Tube with automatic softening device and tin radiator for cooling anticathode. Mueller Tube with water-cooled anticathode and automatic softening device. Transformer Tube. Siemens Bulb with massive anticathode and osmosis softening device. Mueller Bulb with tong method of cooling anticathode. Duplitized extra-oral 5x7 film produced to obtain greater speed and contrast. 1920 A machine-wrapped periapical film packet placed on the market. Courses in Radiodontics given in forty schools. The remaining five schools did not offer any separate and distinct course. General Electric Research Laboratory announced the development of a shockproof dental X-ray unit, in which both the hot-cathode tube and the high-voltage transformer were oil immersed in the same metal container. 1921 Machine-made packet introduced. 1924 Dr. Howard R. Raper originated the intra-oral method of radiographing both upper and lower teeth on a single bite-wing film, known today as the interproximal X-ray examination. 1925 Introduction of safety base of cellulose acetate for dental X-ray film and intra-oral periapical radiatized film packet. 1926 Telephotograph, first Dental sciagraph, transmitted by wire from New York to Chicago. 1928 Dr. Clarence O. Simpson outlined the placement of X-ray packets in taking a full series. 1929 White film packets produced. 1930 Small periapical film for children, termed Number O, introduced. 193 5 The Curriculum Survey Committee recommended thirty-four hours of instruction in Radiodontics. 1938 Rapid-processing periapical film manufactured. 1940 All dental schools required students to know procedures involved in taking radiographs, from which diag- nostic interpretations must be made. 1941 Announcement of ultra-speed periapical dental film. 1945 Bite-wing film with radiatized emulsion introduced. 1946 Dr. George Karn outlined the precision placement of film packets, in detail, in taking a full series. 1915 1916 1917 1918
Are you trying to find old school friends, old classmates, fellow servicemen or shipmates? Do you want to see past girlfriends or boyfriends? Relive homecoming, prom, graduation, and other moments on campus captured in yearbook pictures. Revisit your fraternity or sorority and see familiar places. See members of old school clubs and relive old times. Start your search today!
Looking for old family members and relatives? Do you want to find pictures of parents or grandparents when they were in school? Want to find out what hairstyle was popular in the 1920s? E-Yearbook.com has a wealth of genealogy information spanning over a century for many schools with full text search. Use our online Genealogy Resource to uncover history quickly!
Are you planning a reunion and need assistance? E-Yearbook.com can help you with scanning and providing access to yearbook images for promotional materials and activities. We can provide you with an electronic version of your yearbook that can assist you with reunion planning. E-Yearbook.com will also publish the yearbook images online for people to share and enjoy.
