Surveying Instrument Collection
|
Maker |
Wild, Heerbrugg (Switzerland) |
|
Model |
NK2 |
|
Serial Number |
136801 |
|
Dimensions |
Telescope length 195mm, Width 120mm, Height 140mm |
|
Image |
|
|
Description |
This Wild NK2 tilting level is an accurate, quick to use instrument for top quality work. The telescope features 26x magnification with an inverted bright image permitting staff readings of high accuracy. It also features a reversible tubular level and telescope, which allows the divergence between the line of collimation and the bubble tube axis at two staff readings (180º apart) to be automatically eliminated by taking the mean of the two readings. This particular model, is fitted with a horizontal circle to allow it's use for setting-out angles and for tacheometric surveys in reasonably level terrain, and the reading microscope is situated to the right of, and below, the telescope. The glass circle is divided into degrees, each degree being numbered, sub-division of the same being made by a secondary scale with 6 intervals for 360 degree division. The lowest long line of the scale is the index. The scale serves for accurate reading of the distance between the index line and the division line of the circle crossing the scale. One interval of the scale amounts to 10 minutes and single minutes are read quickly and accurately by estimating tenths of the scale interval. The level features a high-performance telescope with coated optics, internal focusing, and stadia lines for distance measurement. The controls (fine drive, bubble and circle readings) are sited to place them within easy reach of the observer. The main disadvantage of tilting levels is that before each reading is made, the tubular bubble must be set correctly. This is due to the absence of a compensator. The precision of a 1km double levelling run is quoted as ±2mm. The sensitivity of the level bubble is 30"/2mm and the accuracy of levelling the line of sight is ±0.75". |
|
History & comments |
There is no historical information available. |
|
Conservation |
In metal container (L 230mm, W 140mm, H 180mm) |
|
Condition |
Good condition (well maintained) |
|
Remarks |
|
|
Dates |
Manufactured in 1964. Catalogued in 2000 and 2005 |
