Troughton & Simms 6-inch theodolite · 1888
London-built 6-inch transit theodolite, silvered circles, all axes free. Original mahogany case, later oak tripod.
- SKU
- MS-SC-1007
- Era
- Pre-1900
- Condition
- All axes free, optics clear, silvered circles legible, tripod later replacement
- Dimensions
- Instrument 12" tall, case 15" × 12" × 11"
- Weight
- 14 lbs (instrument), 24 lbs cased
- Provenance
- From a defunct Yorkshire mining survey office, 2018
- Category
- Scientific Instruments
- Tags
- theodolitetroughton-simmssurveyingtransitvictorian
A Troughton & Simms of Fleet Street six-inch transit theodolite, signed and dated 1888 on the horizontal circle. Silvered circles reading to 20 seconds by Vernier, a striding level for the transit axis, and a compass housed in the lower plate. All three axes are free and hold their adjustment; the telescope optics are clear enough for daylight sighting on distant chimneys.
Troughton & Simms held the Ordnance Survey contract for most of the nineteenth century, and while this is a private-order instrument rather than a Trig point piece, it's cut from the same cloth. The bronze is patinated to a warm chocolate; the silver still reads without effort.
Original fitted mahogany case with all three plumb bobs and the sunshade. Tripod is a later English oak replacement, well matched.
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