Define Tacheometry. Write down it's Purpose and Uses.

Tacheometry is the branch of angular surveying in which both horizontal and vertical distances between the stations of observation and staff positions are determined from instrumental observation (i.e, by angular observation with a tacheometer) without necessity of chaining. 

A tacheometer is a transit theodolite having a stadia telescope fitted with two horizontal hairs called Stadia hairs in addition to the usual cross hairs.

The primary objective of tacheometry is the preparation of contoured plans and traversing. It is assumed to be rapid and accurate method in rough country and has thus been widely used by engineers/surveyors in location surveys for railways, canals, resorvoirs etc. For surveys of high accuracy, tacheometry provides a good check on the distances measured with tapes/chains.

Tacheometry is used for:

1. Preparation of a topographic maps where both horizontal and vertical distances a....

Tacheometry is the branch of angular surveying in which both horizontal and vertical distances between the stations of observation and staff positions are determined from instrumental observation (i.e, by angular observation with a tacheometer) without necessity of chaining. 

A tacheometer is a transit theodolite having a stadia telescope fitted with two horizontal hairs called Stadia hairs in addition to the usual cross hairs.

Purpose Of Tacheometric Survey:

The primary objective of tacheometry is the preparation of contoured plans and traversing. It is assumed to be rapid and accurate method in rough country and has thus been widely used by engineers/surveyors in location surveys for railways, canals, resorvoirs etc. For surveys of high accuracy, tacheometry provides a good check on the distances measured with tapes/chains.

USES OF Tacheometry:

Tacheometry is used for:

1. Preparation of a topographic maps where both horizontal and vertical distances are required to be measured.
2. Survey work in difficult terain where direct methods of measurements are inconvinient.
3. Reconnaissance survey for highways and railways.
4. Establishment of secondary control points.

It is best suited when obstacles such as steep and broken ground, deep ravines, and stretches of water or swamps are met with.

ADVANTAGES OF TACHEOMETRY:

1. Both the horizontal distances and difference of elevation are determined indirectly in tacheometry surveying.
2. Tacheometric methods can be used in terrain, where direct methods are inconvenient.
3. There is considerable saving in time and moneywith the use of tacheometric methods.
4. It can be widely used for reconnaissance surveys of routes, for hydrographic surveying and for filling in details in a traverse.