(a) Describe the surveyor's chain (b) Outline any three problems that could be encountered in...
(a) Describe the surveyor's chain
(b) Outline any three problems that could be encountered in the use of the surveyor's chain.
Explanation
(a)Describe the surveyor's chain
Surveyor's chain is 100ft long (engineer chain) 66ft long — gunter chain made of steel wires connected by a set of oval links. The links are marked by brass tags which are numbered 5,10, 15, 20, 25, 30, 35, etc, and lengths from the middle ring between two bars to the next one is equally linked. The chain has brass handles attached to each end. A link is the distance from the middle of the centre ring to the middle of the next central ring. .
(b)Problems in the use of Surveyor's Chain
(1) Inaccuracy of measurement as a result of bending of any of the steel wires.
(2) Sagging of chain during use.
(3) Any obstacle along the line of chain
(4) There is limit to the area that could conveniently be surveyed with the chain.
(5) Chain survey cannot be used for enclosed, built-up and bush covered areas.
(6) Marshy / broken ground make chaining slow and difficult.
(7) Difficult to carry about.