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Description: | Ramsden's patent (No.1112, 1775, Dec.30) Astronomical Equatorial Instrument with glazed Sheraton case, c.1775. Refracting telescope, 2-1/4 inch aperture and 18-inch focal length (probably by Peter Dollond), on an adjustable equatorial mounting with tripod stand. The stand is equipped with 3 spirit levels, 3 levelling screws and 2 scales read by verniers. Accessories include 5 eyepieces, two diagonal mirrors, glass prism, two dark filter caps and a filar micrometer with reflector to illuminate the cross hairs. | License: | http://creativecommons.org/licenses/by-nc-sa/2.5/ | Subjects: | equatorial instrument filar micrometer telescope - refracting | Temporal: | 1770-1780 | Source: | Science Museum | Creator: | Dollond, Peter | Identifier: | http://collectionsonline.nmsi.ac.uk/grab... | Go to resource |
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