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William Herschel's reflecting telescope of 40 ft (12 m) focal length, 1789 (1807). Artist: Unknown - Album alb4003310
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Astronomy: a 40-foot telescope constructed by William Herschel, in use outdoors. Coloured etching, 18--. | Wellcome Collection
![The William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE) is now being installed at the WHT in La Palma | ICCUB The William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE) is now being installed at the WHT in La Palma | ICCUB](https://icc.ub.edu/sites/icc/files/styles/card_600x400/public/media/imatge/2021-10/WEAVE_FIBRE_POSITIONER.png?h=532f109e&itok=_9q6fdaY)
The William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE) is now being installed at the WHT in La Palma | ICCUB
![Sir William Herschel Great 40 foot telescope reflecting telescopes 1785 1789 Observatory House Slough England primary mirror Stock Photo - Alamy Sir William Herschel Great 40 foot telescope reflecting telescopes 1785 1789 Observatory House Slough England primary mirror Stock Photo - Alamy](https://c8.alamy.com/comp/C8NAJN/sir-william-herschel-great-40-foot-telescope-reflecting-telescopes-C8NAJN.jpg)