.jpg?w=1)
细节
A late 18th-Century lacquered-brass crystal micrometer eyepiece set,
signed on the 3¾-inch vertical circle T. Slater Optician 10 Wallbrook St New North Road London, with silvered circumference scale and twin verniers with worm-screw adjustment and clamp, the eyepiece tube with field lens adjustable via rack and pinion, with five brass caps each with a cell containing a split Icelandic spar crystal, rotated via the vertical circle to produce a double image, also with one empty cap and three terrestrial eyepieces, in a fitted mahogany box with inset brass carrying handle -- 16.2cm. (6 3/8in.) wide; and seven various eyepieces including one with extension tube, one with 45° mirror, and one with parallel fine-hair adjustment with turning wheel with silvered scale, in a mahogany box; another box containing five various extension tubes, one with right-angled eyepiece, a 10-inch long sighting telescope with lens cap and draw-tube focusing, and various mounting components; and a simple periscope, the 13-inch long brass tube with wooden handle, threaded eyepiece adjustment, and 2x magnification
See Illustration (4)
signed on the 3¾-inch vertical circle T. Slater Optician 10 Wallbrook St New North Road London, with silvered circumference scale and twin verniers with worm-screw adjustment and clamp, the eyepiece tube with field lens adjustable via rack and pinion, with five brass caps each with a cell containing a split Icelandic spar crystal, rotated via the vertical circle to produce a double image, also with one empty cap and three terrestrial eyepieces, in a fitted mahogany box with inset brass carrying handle -- 16.2cm. (6 3/8in.) wide; and seven various eyepieces including one with extension tube, one with 45° mirror, and one with parallel fine-hair adjustment with turning wheel with silvered scale, in a mahogany box; another box containing five various extension tubes, one with right-angled eyepiece, a 10-inch long sighting telescope with lens cap and draw-tube focusing, and various mounting components; and a simple periscope, the 13-inch long brass tube with wooden handle, threaded eyepiece adjustment, and 2x magnification
See Illustration (4)
注意事项
No VAT will be charged on the hammer price, but VAT at 17.5% will be added to the buyer's premium which is invoiced on a VAT inclusive basis