Measuring of Vertical Distances

Question 1

the commonly employed method of determining the elevation of points some distance apart by a series of set ups of a leveling instrument along a selected route.

Answer 1

Direct or spirit leveling

Question 2

the process of accurately determining the difference in elevation between two intervisible points located at a considerable distance apart and between which points leveling could not be performed in the usual manner.

Answer 2

Reciprocal leveling

Question 3

used to determine differences in elevation between points at designated short
measured intervals along an established line to provide data from which a vertical section of the ground surface can be plotted.

Answer 3

Profile leveling

Question 4

employed in determining by trigonometric computations the
difference in elevation between two points from measurements of its horizontal or slope distance and the vertical angle between the points.

Answer 4

Trigonometric leveling

Question 5

combines features of direct leveling with those of trigonometric leveling. It
can provide reasonable accuracy for preliminary surveys, mapping, and rough leveling where quick measurements are needed.

Answer 5

Stadia leveling

Question 6

involves the determination of the differences in elevation between
points by measuring the variation in atmospheric pressure at each point by means of a barometer.

Answer 6

Brometric leveling

Question 7

Short profiles at right angles to the line of work are usually plotted at
regular intervals for this purpose.

Answer 7

Cross-section leveling

Question 8

method of determining the relative elevations of points in borrow-pit
excavations for the purpose of calculating volumes of earthwork.

Answer 8

Borrow-pit leveling

Question 9

It is the most widely used direct leveling instrument. It has a long telescope
which is rigidly attached to the level bar.

Answer 9

Dumpy level

Question 10

It has a detachable telescope which rests in supports called wyes. It can be removed from the Y-shaped supports and turned end for end during adjustment by releasing the two clamping collars which fit across the tops of the Y’s.

Answer 10

Wye level

Question 11

used primarily in the different phases of building construction where a high
degree of precision is not a primary requisite.

Answer 11

Builder’s level

Question 12

It has become popular for conventional leveling work because of the ease
and speed of their operation. It does not use a level vial and its ability to level itself depends upon the action of a complex pendulum-and-prism device.

Answer 12

Automatic level

Question 13

commonly employed for very precise leveling operations and in other general leveling work.

Answer 13

Tilting level

Question 14

employed in first-order leveling work where extreme precision is an important requirement. It is equipped with stadia hairs in addition to the standard vertical and horizontal cross hairs to make it suitable for three-wire leveling.

Answer 14

Geodetic level

Question 15

universal surveying instrument. It can provide results which are fairly precise although not as good as those obtained with conventional levels.

Answer 15

Transit

Question 16

A laser system is a separate unit equipped with a portable power supply and may be a helium-neon or gas laser.

Answer 16

Laser level

Question 17

a hand-held instrument used on surveys involving short sights and where a low order of accuracy is sufficient.

Answer 17

Hand level

Question 18

a graduated rod which is used for measuring the vertical distance between the line of sight through a leveling instrument and the point whose elevation is either required or known.

Answer 18

Leveling rod

Question 19

a device used for fast and correct plumbing of a leveling rod. It is L-shaped in design and consists of a small circular spirit level fastened to the rod or to a small bracket held against the side of the rod.

Answer 19

Rod level

Question 20

a small device attached to the rod when extremely long sights make direct reading of the rod
difficult or impossible.

Answer 20

Target

Question 21

a metal tube containing a system of lenses which are used to fix the direction of the line sight and in magnifying the apparent size of objects in its field of view. Jan Lippershey, a
Dutchman, invented the first telescope in 1608.

Answer 21

Telescope

Question 22

a compound lens composed of crown and flint glass mounted in the objective end of the telescope and has its optical axis concentric with the tube axis.

Answer 22

Objective lens

Question 23

a form of microscope containing either two or four lenses and is used to enlarge altogether the image and the cross hairs.

Answer 23

Eyepiece

Question 24

consist of a pair of lines which are perpendicular to each other and are used to
define the instrument’s line of sight.

Answer 24

Cross hairs

Question 25

the ratio of the apparent size of an object viewed through a telescope to its size as seen by the unaided eye from the same distance.

Answer 25

Magnification

Question 26

a sealed graduated glass tube containing some amount of liquid and a small air bubble.

Answer 26

Level vial

Question 27

used on most modern and precise instruments such as the tilting and automatic
levels. It employs an optical device which splits the bubble longitudinally, then turns one end around to make it appear adjacent to the other end.

Answer 27

Coincidence bubble

Question 28

serve as abase to prevent movement of the instrument after it is set up.

Answer 28

Tripods

Question 29

Steps in taking a rod reading.

Answer 29

1. Position the rod
2. Focus on the rod
3. Read the rod