1.25-inch pocket refracting telescope
Date: 1760-1780
Inventory Number: 5003
Classification: Telescope
Maker: John Gilbert (II) (fl. 1751-1791)
Owner: Edward Holyoke ? (1689 - 1769)
Owner: Edward Augustus Holyoke (1728 - 1829)
Cultural Region:
Place of Origin:
Dimensions:
with telescope horizontal, focus line 2: 14.3 × 8.5 × 15.3 cm (5 5/8 × 3 3/8 × 6 in.)
telescope tube closed: 4.4 × 4.4 × 12.2 cm (1 3/4 × 1 3/4 × 4 13/16 in.)
Accessories: folding tripod (stored inside); dust cap
DescriptionElegant miniature brass refracting telescope with 1 draw tube and folding library mount.
The telescope has an aperture of 1 1/4 inches (3.2 cm) with an achromatic lens. The lens screws into the end of the tube. A draw tube fits into the other end. The draw tube has a tapered tailpiece that is threaded to it. The tailpiece has a small-aperture stop.
An eyepiece threads into the tailpiece. It has a revolving wheel with different powers of oculars marked 1- 4 in a small window. The draw tube is encircled with four lines marked 1, 2, 3, 4 corresponding to focusing positions for each lens chosen. The eyepiece also has a swing-away dark red filter.
The main tube has a bracket for attaching the altazimuth mount. The mount screws into a tapered pillar, which in turns screws into a base with three cabriole legs.
When not in use, the mount and pillar are unscrewed from the tripod platform, and screwed to its underside. The legs folds up around the pillar and mount. This assembly then slides into the draw tube, where it is threaded to the end. The draw tube is then inserted into the main barrel.
The telescope has an aperture of 1 1/4 inches (3.2 cm) with an achromatic lens. The lens screws into the end of the tube. A draw tube fits into the other end. The draw tube has a tapered tailpiece that is threaded to it. The tailpiece has a small-aperture stop.
An eyepiece threads into the tailpiece. It has a revolving wheel with different powers of oculars marked 1- 4 in a small window. The draw tube is encircled with four lines marked 1, 2, 3, 4 corresponding to focusing positions for each lens chosen. The eyepiece also has a swing-away dark red filter.
The main tube has a bracket for attaching the altazimuth mount. The mount screws into a tapered pillar, which in turns screws into a base with three cabriole legs.
When not in use, the mount and pillar are unscrewed from the tripod platform, and screwed to its underside. The legs folds up around the pillar and mount. This assembly then slides into the draw tube, where it is threaded to the end. The draw tube is then inserted into the main barrel.
Signedon draw tube: Gilbert / Towerhill / London
FunctionThis is a pocket telescope with a folding library-table mount.
ProvenanceEdward Augustus Holyoke; ... ; Andrew Nichols, a descendent of Holyoke, pre-1975; David P. Wheatland, 1975.