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William Coolidge: Vacuum Tube for X-Ray Production, 1926

Patent Discussions

Below, you will find correspondence about Coolidge Tube patents. At right, there are three listings of Coolidge's patents.

CSA Secretary to Palmer
Committee Secretary to Frederic Palmer, Jr., Reporting difficulty in locating specific Coolidge Tube patent, suggesting comparison with an actual tube, 4/16/1926. (520K)

Palmer to CSA Secretary
Frederic Palmer, Jr. to Committee Secretary, Pointing out a disagreement between the patent dates supplied and those etched on Palmer's own Coolidge tube, 4/19/1926. (222K)
Page 2 (161K)

Committee Secretary to Palmer
Committee Secretary to Frederic Palmer, Jr., Reporting on unsuccessful patent search and the remedy of contacting Dr. Whitney for details, 4/21/1926. (575K)

Palmer to Committee Secretary
Frederic Palmer, Jr. to Committee Secretary, Discussing the difficulties finding patent dates, indicating informal opinion that Coolidge be awarded the Potts Medal, 4/22/1926. (450K)

Whitney to Hoadley
Willis R. Whitney to George A. Hoadley, Supplying the definitive patent data on the Coolidge Tube, 4/22/1926. (651K)

Committee Secretary to Palmer
Committee Secretary to Frederic Palmer, Jr., Agreeing on the suitability of the Potts Medal award, promising to keep updated on patent situation, and scheduling future meetings, 4/23/1926. (570K)

Committee Secretary to Whitney
Committee Secretary to Willis R. Whitney, Expressing thanks for the number of the fundamental patent on the Coolidge Tube, 4/23/1926. (200K)

Notecard
Handwritten notes listing patent details referencing X-Ray tube developments (four cards), no date. (502K)