Lebanese International University

School of Engineering

Department of Surveying

SURV563

Surveying II

Lecture notes

Ver.: Beta

Dr. Sami Makdissi

Beirut -2013

1

1 Introduction

1.1 Basic definitions.

In order to gain a clear understanding of the procedures for making surveying

measurements on the earth’s surface, it is necessary to be familiar with the

meaning of certain basic terms:

1. A vertical line at any point on the earth’s surface is the line that follows the

direction of gravity at that point. It is the direction which a string will

assume if a weight is attached to the string and the string is suspended

freely at the point. At a given point there is only one vertical line.

2. A horizontal line at a point is any line that is perpendicular to the vertical

line at the point. At any point there are an unlimited number of horizontal

lines.

3. A horizontal plane at a point is the plane that is perpendicular to the

vertical line at the point. There is only one horizontal plane through a given

point.

4. A vertical plane at a point is any plane that contains the vertical line at the

point. There is unlimited number of vertical planes at a given point.

5. A level surface is a continuous surface that is, at all points, perpendicular to

the direction of gravity. It is exemplified by the surface of a large body of

water at complete rest. For a small portion of the earth’s surface the level

surface can be regarded as a horizontal plane.

6. A horizontal distance (HD) between two given points is the distance

between the points projected onto a horizontal plane. The horizontal

plane, however, can be defined at only one point. For a survey, the

reference point may be taken as any one of the several points of the

survey.

2

7. A horizontal angle (HA) is an angle measured in a horizontal plane between

two vertical planes.

8. A vertical angle (VA) is an angle measured in a vertical plane. By

convention, if the angle is...