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Compass surveying is a branch of surveying in which directions of surveying lines are determined with a compass and the length of lines are measured with a tape or chain. In practice the compass is  generally used to run a traverse. In surveying, "Traverse" consists of a series of straight lines connected together to form a open or a closed polygon. Methods of traversing: Depending on the type of instrument used for the measurement of angles the method of Traversing can be classified as under; 1.Chain Traverse 2.Compass Traverse. 3.Plane Table Traverse. 4.Stadia Traverse. 5.Theodolite Traverse. IN Compass Traverse the direction of the traverse lines are determined with a magnetic compass. The magnetic Compass may be "SURVEYOR COMPASS" OR "PRISMATIC COMPASS" PRISMATIC COMPASS: The prismatic compass is one of the magnetic compass in which there is a prism for taking observations. The prismatic compass is generally smaller in size than a surveyor  compass. T

A contour is defined as an imaginary line of constant elevation on the ground surface. It can also be defined as the line of intersection of a level surface with the ground surface. For example, the line of intersection of the water surface of a still lake or pond with the surrounding ground represents a contour line.                                                                                                   It facilitates depiction of the relief of terrain in a two dimensional plan or map. The process of tracing contour lines on the surface of earth is called contouring. A contour map gives the idea of the altitudes of the surface features as well as their relative positions in a plan CONTOURING BY INDIRECT METHOD: The points surveyed are not necessarily on the contour lines but spot levels taken along with series of lines laid over the area. The position of spot levels is plotted on the plan and contours drawn by interpolation. BY SQUARES: In this method the whole area is div

Chain survey is the simplest method of surveying. In this survey only measurements are taken in the field, and the rest work, such as plotting calculation etc. are done in the office. This is most suitable adapted to small plane areas with very few details. If carefully done, it gives quite accurate results. The necessary requirements for field work are chain, tape, ranging rod, arrows and some time cross staff. Survey Station: Survey stations are of two kinds Main Stations Subsidiary or tie Main Stations: Main stations are the end of the lines, which command the boundaries of the survey, and the lines joining the main stations re called the main survey line or the chain lines. Subsidiary or the tie stations: Subsidiary or the tie stations are the point selected on the main survey lines, where it is necessary to locate the interior detail such as fences, hedges, building etc. Tie or subsidiary lines: A tie line joints two fixed points on the main survey lines. It helps to checking the

Plane table is a graphical method of surveying in which the field works and the plotting is done simultaneously. It is particularly adopting in small mapping. Plane table surveying is used for locating the field computation of area of field. Merits: It is most suitable for preparing small scale map or surveying small area. It is most rapid method. Field book is not necessary. No great skill is required for satisfactory map. It is particularly suitable for magnetic area where prismatic compass is not reliable. Contour and irregular object may be represented accurately. It is less costly. Demerits: Plane Table Essentially a tropical instruments. It is not suitable to work in wet climate. There are several accessories to be carried out and therefore they are likely to be lost. It is not suitable for accurate work. Parts of plane Table: Plane table essentially consist of Drawing board mounted on tripod. Alidade.

it is a measuring device used for land survey. Gunter divided the chain into 100 links, marked off into groups of 10 by brass rings which simplified intermediate measurement. On the face of it, the dimensions make no sense: Each link is 7.92 inches long; 10 links make slightly less than 6 feet 8 inches and a full length of 66 feet. In fact, he had made a brilliant synthesis of two incompatible systems, the traditional English land measurements, based on the number 4, and the newly introduced system of decimals based on the number 10.