File:PSM V17 D023 Microphone and speaker by elisha gray 1874.jpg
Size of this preview: 799 × 359 pixels. Other resolutions: 320 × 144 pixels | 640 × 288 pixels | 1,609 × 723 pixels.
Original file (1,609 × 723 pixels, file size: 59 KB, MIME type: image/jpeg)
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 03:53, 20 February 2014 | 1,609 × 723 (59 KB) | Ineuw | Improved image contrast | |
01:37, 28 September 2013 | 1,636 × 757 (50 KB) | Ineuw | {{Information |Description = Microphone and speaker by Elisha Gray 1874 |Source = [http://www.archive.org/details/popularsciencemo17newy Popular Science Monthly Volume 17] |Date = 1880 |Author = {{unknown|Author}} |Permission = {{PD-old}} |other_... | ||
03:43, 16 August 2010 | 1,624 × 739 (61 KB) | Ineuw | {{Information |Description = Microphone and speaker by Elisha Gray 1874 |Source = http://en.wikisource.org/wiki/Page:Popular_Science_Monthly_Volume_17.djvu/23 |Date = 1880 |Author = Unknown |Permission = {{PD-old}} |other_versions = }} [[Category: |
File usage
The following 2 pages use this file: