| George Adams - 1813 - 576 pages
...hole made in the vane ; when this wire coincides with the horizontal wire of the telescope, it shews the height of the apparent level above the ground at that place. OF LEVELLING. Levelling is the art which instructs us in fmding how much higher or lower any given... | |
| Frederick Walter Simms - 1834 - 124 pages
...shown in the annexed figure : this vane being raised or lowered by the assistant, until the cross wire corresponds .with the horizontal wire of the telescope,...be set up at equal .distances on each side of the spirit-level : the difference of the heights of their vanes •will be the absolute difference of level... | |
| Frederick Walter Simms - 1834 - 134 pages
...shown in the annexed figure : this vane being raised or lowered by the assistant, until the cross wire corresponds with the horizontal wire of the telescope,...the apparent level above the ground at that place. 1 When both the staves are used, they should be set up at equal distances on each side of the spirit-level... | |
| Frederick Walter Simms - 1836 - 160 pages
...GRAVATT'S construction, will scarcely ever need being repeated. OF THE LEVELLING STAVES. LEVELLING-STAVES. the telescope, the height of the wire in the vane,...should be set up at equal distances on each side of the spirit-level : the difference of the heights of their vanes will be the absolute difference of level... | |
| Frederick Walter Simms - 1844 - 178 pages
...sliding vane, with a wire placed across a square hole in the centre, as shown in the annexed figure : this vane being raised or lowered by the assistant,...should be set up at equal distances on each side of the spiritlevel : the difference of the heights of their vanes will be the absolute difference of level... | |
| Basil Jackson - 1847 - 410 pages
...shown in the annexed figure; the vane being raised or lowered by the assistant until the cross wire corresponds with the horizontal wire of the telescope,...the apparent level above the ground at that place. rv When both the staves are used they should be set up at equal distances on each side of the spirit-level... | |
| Frederick Walter Simms - 1850 - 184 pages
...sliding vane, with a wire placed across a square hole in the centre, as shewn in the annexed figure : this vane being raised or lowered by the assistant,...the apparent level above the ground at that place. j=, 1 When both the staves are used, they should be MJ set up at equal distances on each side of the... | |
| Basil Jackson - 1853 - 420 pages
...shown in the annexed figure; the vane being raised or lowered by the assistant until the cross wire corresponds with the horizontal wire of the telescope,...should be set up at equal distances on each side of the spirit-level ; the difference of the heights of their vanes will be the absolute difference of level... | |
| Robert Hirsch - 2008 - 416 pages
...pictures outside, on a clear day, in direct 282 ' ' i, I ' / f f - - r 9.8 When copying work, two lights should be set up at equal distances on each side of the camera at 45-degree angles to the work being copied. Meter from a gray card, not off the surface of... | |
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