Search Images Maps Play YouTube News Gmail Drive More »
 Books Books
First, make the centre of the horizontal wire coincide with some well-defined part of a distant object; then turn the telescope half round in its Y's till the level lies above it, and observe if the same point is again cut by the centre of the wire ;...
A Treatise on Surveying and Civil Engineering, Wherein Everything that is ... - Page 23
by P. O'Shaughnessy (Civil engineer) - 1848 - 98 pages

## A treatise on the principal mathematical instruments employed in surveying ...

Frederick Walter Simms - 1834 - 124 pages
...during an entire revolution of the telescope. The usual method of making this adjustment is as follows : First, make the centre of the horizontal wire coincide...Y's till the level lies above it, and observe if the same point is again cut by the centre of the wire ; if not, move the wire one half the quantity of...

## Practical Geodesy: Comprising Chain Surveying, and the Use of Surveying ...

sir J Butler Williams - 1846 - 368 pages
...vertically. This adjustment is effected as follows: — Make the intersection of the cross wires to coincide with some well-defined part of a distant...half round in its Y's, till the level lies above it ; if the same point be not then covered by the centre of the wires, move this centre one-half of the...

## A Treatise on Military Surveying: Including Sketching in the Field, Plan ...

Basil Jackson - 1847 - 412 pages
...the theodolite on its legs, and direct the telescope so that the centre of the horizontal hair shall coincide with some well-defined part of a distant object ; then turn the telescope in the Ys till the level is uppermost : observe then whether the horizontal hair still coincides with...

## Pike's Illustrated Descriptive Catalogue of Optical, Mathematical, and ...

Benjamin Pike - 1848 - 356 pages
...during an entire revolution of the telescope. The usual method of making this adjustment is as follows : First, make the centre of the horizontal wire coincide...Y's till the level lies above it, and observe if the same point is again cut by the centre of the wire ; if not, move the wire one half the quantity of...

## Pike's Illustrated Descriptive Catalogue of Optical, Mathematical and ...

Benjamin Pike (Jr.) - 1848 - 484 pages
...during an entire revolution of the telescope. The usual method of making this adjustment is as follows : First, make the centre of the horizontal wire coincide...Y's till the level lies above it, and observe if the same point is again cut by the centre of the wire ; if not, move the wire one half the quantity of...

## A Manual of Surveying for India, Detailing the Mode of Operations on the ...

Ralph Smyth, Sir Henry Edward Landor Thuillier - 1851 - 828 pages
...adjustment is as follows : First, make the centre of the horizontal wire coincide with some well defined part of a distant object ; then turn the telescope...Y's till the level lies above it, and observe if the same point is again cut by the centre of the wire ; if not, move the wire one-half the quantity of...

## The Practice of Engineering Field Work, Applied to Land, Hydrographic, and ...

W. Davis Haskoll - 1858 - 324 pages
...question. To adjust the line of collimation. " First make the intersection of the horizontal wires coincide with some well-defined part of a distant object, then turn the telescope half round in its ' y-»- till the level lies above it, and observe if the same point is again cut by the centre of the...