At the base of the Exotic Garden's cliff, 100 m above the ground, an underground cavity opens into the Observatory Cave. The calcareous rock was hollowed out by water rich in carbon dioxide and the cave is full of caverns complete with amazing structures: stalactites, stalagmites, curtains, columns, spaghetti-like helictites and much more. he camera obscura projects a panoramic view of the surrounding area onto a white surface inside a darkened room. A box on top of the building contains a convex lens and sloping mirror. Light is reflected vertically downward onto the table, giving a true (not mirror) image. The technique, which originated in the 16th Century, gives best results on bright days. William West in an advertisement of June 1830 described it as 'embracing the whole of the surrounding scene from the gallery to the horizon'. He also offered use of achromatic and Newton telescopes and an astronomical clock. The present owners have recently been granted planning permission to build a dome to replicate a 19th century one which will contain a viewing terrace. The picture below shows how close the Observatory is to the Suspension Bridge, which crosses the gorge to the right of the photo. There is, however, another feature close by - St Vincent's Cave, sometimes known as the Giant's or Ghyston's Cave. It can just be made out at the bottom right of the picture, some 250 feet above the valley floor. The observatory hill itself is 338 feet above the river's normal high water mark.
The Observatory (grid reference ST564733) is a former mill, now used as an observatory, located on Clifton Down, close to the Clifton Suspension Bridge, Bristol, England. At 337 feet (92 metres) above the gorge, the cliff top is likely to have been used as a lookout post since at least the Iron Age. The building was erected with the permission of the Society of Merchant Venturers, as a windmill for corn in 1766 and later converted to the grinding of snuff, when it became known as the 'The Snuff Mill'. This was damaged by a fire on October 30th 1777, when the sails were left turning during a gale and caused the equipment to catch light. It was then derelict for 52 years until in 1828 William West, an artist, rented the old mill, for 5 shillings (25p) a year, as a studio. In 1977, the Merchant Venturers sold the observatory to Honorbrook Inns, however they were obliged to maintain public access to the camera obscura whose ownership was retained by the Merchant Venturers It has been designated by English Heritage as a grade II* listed building[3] and is currently on the Buildings at Risk Register West installed telescopes and a camera obscura, to help students from the Bristol School of Artists, who used it to draw the Avon Gorge and Leigh Woods on the opposite side,many examples of these paintings can be seen in Bristol City Museum and Art Gallery. The pictures which originated from images within the camera obscura he called 'photogenic drawing' and were based on the work of William Fox Talbot. A 5" (13cm) convex lens and sloping mirror was installed on the top of the tower which project the panoramic view vertically downward into the darkened room below. Visitors view the true image (not mirror image) on to a fixed circular table 5 feet (1.5m) in diameter, with a concave metal surface, and turn the mirror by hand to change the direction of view.
West installed telescopes and a camera obscura, to help students from the Bristol School of Artists, who used it to draw the Avon Gorge and Leigh Woods on the opposite side,many examples of these paintings can be seen in Bristol City Museum and Art Gallery. The pictures which originated from images within the camera obscura he called 'photogenic drawing' and were based on the work of William Fox Talbot. A 5" (13cm) convex lens and sloping mirror was installed on the top of the tower which project the panoramic view vertically downward into the darkened room below. Visitors view the true image (not mirror image) on to a fixed circular table 5 feet (1.5m) in diameter, with a concave metal surface, and turn the mirror by hand to change the direction of view. Once we stepped back into reality, Professor Zuffo gave us a tour of the media engineering lab, and the Digital TV project that they're developing. As you can imagine, most of Brazil still receives their TV signal over the air, and Professor Zuffo's team is developing a low cost set-top box that will bring the digital TV experience to the masses: This is located inside the Exotic Garden itself. Large-scale work has made it possible to adapt this cave so that visitors may admire, 60 metres under the ground, a prehistoric dwelling and magnificent limestone concretions with peculiar shapes, shown to advantage by the effects of the lighting.
