![C.J. Edwards, J.C. Eberhardt (Dayton Aeroplane Club), aviation enthusiast William J. Hammer, and R. Joseph Collier (1876-1918), publisher and president of the Aero Club of America, at Wilbur Wright's funeral ca. 1912 C.J. Edwards, J.C. Eberhardt (Dayton Aeroplane Club), aviation enthusiast William J. Hammer, and R. Joseph Collier (1876-1918), publisher and president of the Aero Club of America, at Wilbur Wright's funeral ca. 1912](https://l450v.alamy.com/450v/2bbymgk/cj-edwards-jc-eberhardt-dayton-aeroplane-club-aviation-enthusiast-william-j-hammer-and-r-joseph-collier-1876-1918-publisher-and-president-of-the-aero-club-of-america-at-wilbur-wrights-funeral-ca-1912-2bbymgk.jpg)
C.J. Edwards, J.C. Eberhardt (Dayton Aeroplane Club), aviation enthusiast William J. Hammer, and R. Joseph Collier (1876-1918), publisher and president of the Aero Club of America, at Wilbur Wright's funeral ca. 1912
![Radium, and Other Radio-active Substances; Polonium, Actinium, and Thorium. With a Consideration of Phosphorescent and Fluorescent Substances, the ... of Disease by the Ultra-violet Light: Hammer, William Joseph 1858-1934: 9781371211493: Amazon.com: Books Radium, and Other Radio-active Substances; Polonium, Actinium, and Thorium. With a Consideration of Phosphorescent and Fluorescent Substances, the ... of Disease by the Ultra-violet Light: Hammer, William Joseph 1858-1934: 9781371211493: Amazon.com: Books](https://images-na.ssl-images-amazon.com/images/I/41ucph-G5fL._SX313_BO1,204,203,200_.jpg)
Radium, and Other Radio-active Substances; Polonium, Actinium, and Thorium. With a Consideration of Phosphorescent and Fluorescent Substances, the ... of Disease by the Ultra-violet Light: Hammer, William Joseph 1858-1934: 9781371211493: Amazon.com: Books
![File:Front cover; Radium, Selenium, Ultra-Violet Light etc Wellcome L0074514.jpg - Wikimedia Commons File:Front cover; Radium, Selenium, Ultra-Violet Light etc Wellcome L0074514.jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Front_cover%3B_Radium%2C_Selenium%2C_Ultra-Violet_Light_etc_Wellcome_L0074514.jpg/405px-Front_cover%3B_Radium%2C_Selenium%2C_Ultra-Violet_Light_etc_Wellcome_L0074514.jpg)
File:Front cover; Radium, Selenium, Ultra-Violet Light etc Wellcome L0074514.jpg - Wikimedia Commons
![Radium cartoons. Box 59, folder 2, William J. Hammer Collection, Archives Center. Courtesy of the National Radium cartoons. Box 59, folder 2, William J. Hammer Collection, Archives Center. Courtesy of the National](https://www.fulcrum.org/image-service/k643b202h1601667458/full/full/0/default.png)
Radium cartoons. Box 59, folder 2, William J. Hammer Collection, Archives Center. Courtesy of the National
![X098A067], Letter from William Joseph Hammer to Thomas Alva Edison, December 7th, 1894 · Thomas Edison Papers Digital Edition X098A067], Letter from William Joseph Hammer to Thomas Alva Edison, December 7th, 1894 · Thomas Edison Papers Digital Edition](https://edisondigital.rutgers.edu/files/large/X098A067/xy6920.jpg)
X098A067], Letter from William Joseph Hammer to Thomas Alva Edison, December 7th, 1894 · Thomas Edison Papers Digital Edition
![In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation](https://invention.si.edu/sites/default/files/inventors-hammer-william-x-ray-demo-for-daughter-mabel-1902-si-neg-85-8778-750-inline-edit.jpg)
In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation
![In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation](https://invention.si.edu/sites/default/files/inventors-hammer-william-with-wright-flyer-nasm-9A01542-750-inline-edit.jpg)
In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation
![Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903 Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903](https://c8.alamy.com/comp/2CRMT3R/radium-und-andere-radioaktive-substanzen-unter-besonderer-benutzung-eines-von-elektro-ingenieur-william-j-hammer-vor-dem-american-institute-of-electrical-engineers-und-der-american-electrochemical-society-am-17-april-1903-gehaltenen-vortrages-bringt-beschreibung-neuer-wissen-schaftlicher-instrumente-und-apparatesowie-werkzeuge-und-berichtet-berdie-neuesten-fortschritte-der-physikund-elektrotechnik-probenummernsowie-inhaltsverzeichnis-des-vorjhrigenjahrganges-gratis-und-franko-abonnementvierteljhrlich-nur-mk-150-porto-30-pfg-ausland-60-pfg-yidministration-derfachzdtschrit-2CRMT3R.jpg)
Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903
![Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903 Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903](https://c8.alamy.com/comp/2CRMT75/radium-und-andere-radioaktive-substanzen-unter-besonderer-benutzung-eines-von-elektro-ingenieur-william-j-hammer-vor-dem-american-institute-of-electrical-engineers-und-der-american-electrochemical-society-am-17-april-1903-gehaltenen-vortrages-ten-radioakti-vitt-von-der-noch-die-rede-sein-wird-zuzuschreiben-ist-das-vorhandensein-magnetisch-nicht-ablenkbarer-sehrdurchdringender-strahlen-in-der-radiumstrahlung-der-y-strah-len-wurde-zuerst-von-v-i-11-a-r-d-gemacht-diese-y-strahlen-sindden-rntgenstrahlen-vergleichbar-in-fig-4-ist-das-verschiedene-verhalten-der-einzelnenstrahleng-2CRMT75.jpg)
Radium und andere radioaktive Substanzen : unter besonderer Benutzung eines von Elektro-Ingenieur William J. Hammer vor dem American Institute of Electrical Engineers und der American Electrochemical Society am 17. April 1903
![In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation](https://invention.si.edu/sites/default/files/inventors-hammer-william-ac0069-0000017-sepia-teaser-edit.jpg)
In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation
![Workers sitting and standing outside Edison's first lamp factory, including executive staff members in the front row (from left to right) Philip S Dyer, William J Hammer, Francis R Upton, and James Workers sitting and standing outside Edison's first lamp factory, including executive staff members in the front row (from left to right) Philip S Dyer, William J Hammer, Francis R Upton, and James](https://c8.alamy.com/comp/T6YB1G/workers-sitting-and-standing-outside-edisons-first-lamp-factory-including-executive-staff-members-in-the-front-row-from-left-to-right-philip-s-dyer-william-j-hammer-francis-r-upton-and-james-bradley-menlo-park-new-jersey-1880-image-courtesy-us-department-of-energy-san-francisco-california-T6YB1G.jpg)