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SP4 William John Hammer, Nassau, NY on www.VirtualWall.org The Virtual Wall® Vietnam Veterans Memorial Wall
![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)
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
![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
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