Correct Answer - Option 1 : A traveller
Concepts:
A boning rod is an upright pole having a horizontal board at its top, forming a ‘T ‘shaped rod.
They are made in set of three either in which all three are T shaped rods (each of equal size and shape) or two set rods identical to each other and a third one consisting of longer rod with a detachable or movable ‘T’ piece. This third one is called traveling rod or traveler.
Therefore, a traveler is a special type of boning rod in which the horizontal pieces can be moved along a graduated vertical staff, and can be conveniently clamped at any desired height.
Additional Information:
Some terms which are used frequently in setting out works are defined below.
1. Stake: It is a vertical pole which is driven into the ground so as to act as a permanent identification mark. Stakes may be made of timber or steel, etc. Generally, these are pointed at one end to facilitate their anchoring into the ground.
2. Batter-board: This is also known as a slope rail. A batter-board is generally a flat wooden board, which is forced on top of a pin anchored in ground. Nails are driven in this board to indicate the direction of various lines that may give the mark of an excavation, etc. Strings or wires can be stretched between two batter-boards using the nails driven in them.
3. Crosshead: A crosshead consists of two vertical posts of certain height firmly embedded in ground, on each side of the trench with a horizontal rail nailed to these posts across the trench.
4. Sight Rails: The horizontal member of the crosshead, i.e. the timber beam nailed to the posts is referred to as a sight rail.
