Surveying Instrument Collection
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Maker |
Troughton & Simms, London, England |
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Model |
Everest |
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Serial Number |
No. 95 |
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Dimensions |
Telescope length 430mm, Height 370mm |
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Image |
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Description |
This 'Everest' theodolite was donated by the New South Wales Department of Lands. It is classified as a precision micrometer theodolite and is used typically for establishing major triangulation networks. The instrument incorporates three micrometers allowing precise reading of the horizontal circle with accuracies up to one second (1") of arc. The telescope is approximately 430 mm long and is capable of being removed from the instrument without any difficulty. The horizontal circle, with a diameter of 270 mm, is situated at the base of the instrument and is divided into one-degree intervals from 0º to 360º. The vertical circle is divided into two opposing sectors, each graduated by 5 degree intervals commencing with the zero mark at the horizontal axis and extending to 45 degrees above and below this line. An altitude bubble is located next to the vertical circle. The theodolite generally consists of three moving sections. These include the lower horizontal graduated plate, the upper plate and the vertical arc. Each movement is controlled by individual clamps and slow-motion screws. |
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History & comments |
The 'Everest' theodolite was originally designed by Sir George Everest (1790-1866) for surveying in India. |
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Conservation |
In a box |
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Condition |
Good |
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Remarks |
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Dates |
Manufactured in 1890 (approx). Catalogued in 1997 |
