细节
A rare late 17th-Century [?]North Italian compound microscope,
unsigned and undated, made in vellum-covered pasteboard with wooden lens mount and a brass tripod foot -- 13in. (33cm.) high when in use; the optical tube -- 2¼in. (5.6cm.) diameter, 8½in. (22cm.) long when closed; the tripod support -- 4½in. (11.4cm.) high, 2¼in. (5.6cm.) diameter at foot
The optical tube consists of an outer body-tube containing two draw-tubes. All the tubes are constructed from pasteboard, the outer covered with vellum dyed green and decorated with gold tooling in three panels. The inner two are covered with brushed paste paper coloured pink and purple. Both tubes have thick black lines to show the setting for optimum focus.
At the end of the optical tube is the nose-piece made of walnut, which is threaded to screw into a collar fixed to the inside of the body-tube. The objective lens is contained in a screw-on cell at the end of the nose-piece. It is biconvex with a diameter of about ½in. (1.3cm.). The specimen is viewed through a very small hole with a diameter of 0.06in. (0.14cm.). The first draw-tube serves to extend the length of the light path, while the second holds at the lower end a wooden cell (possibly lime wood) for the 1 3/8in. (3.6cm.) diameter; 0.4cm. thick biconvex field lens. This lens is substantially free of colour, with its edge clipped rather than ground smooth. The upper end of the innermost draw-tube has a wooden cell for the eye-lens (a replacement).
The optical tube is supported in a brass collar with a tripod base, the splayed legs made of thin brass, whose edges are cut with scrolls. Between the legs is a brass support for a wooden specimen holder that is held by a pair of metal straps. At the middle an ivory cell is fitted, which has a plano-concave glass disc to act as a wet cell. The collar is lined with fine cloth to form a grip for the optical tube.
See Colour Illustration and Detail
出版
TURNER, G. L'E., "Three late-seventeenth century Italian Telescopes, two signed by Paolo Belletti of Bologna", Annali dell'Istituto e Museo di Storia della Scienza di Fierenze, 9, part 1 (1984) pp.41-64, xxi plates