Planimeter is an instrument used in surveying to compute the area of any given plan. Planimeter only needs plan drawn on the sheet to calculate area.

 

A pantograph is a system of mechanical linkages which reproduces the motion of one point of the linkage at a second point, usually at an increased or decreased size.

 

These tables consist of a smooth table surface mounted on a sturdy base. The table can be precisely leveled because of the connection between the table top, using bubble levels, in a horizontal plane. A tripod like base is designed to support the table over non-plain surfaces of land. The table can be leveled by adjusting the length of the legs, regardless of the roughness of the terrain. Prominent Usages of our range are:

•In use, a plane table is set over a point and brought to precise horizontal level

•A drawing sheet is attached to the surface and an alidade is used to sight objects of interest

•The alidade, in modern examples of the instrument a rule with a telescopic sight, can then be used to construct a line on the drawing that is in the direction of the object of interest

•By using the alidade as a surveying level, information on the topography of the site can be directly recorded.

 

They are also called marking or chaining pins, and are used to mark the end of each chain during the process of chaining. They are made of good quality metallic wires of 4 mm in diameter and of a minimum tensile strength of 700N/ mm2. The wire is black enameled. The arrows are made 400 mm in length, are pointed at one end for inserting into the ground and bent into a ring at the other end for facility of carrying. They should have a piece of white or red tape tied to the ring so that they can be made easily visible at a distance. To mark the end of each chain length, the arrow is inserted in the ground, but when the ground is hard, a scratch may be made with the pointed end.

 

Wooden pegs are used to mark the positions of stations. They are made of hard timber and are tapered at one end they are usually, 2.5 cm square and 15 cm long, but in soft ground, pegs 40 to 60 cm long and 4 to 5 cm square suitable.