Match the following, in the context of the leveling staff. a. Self-reading staff 1. The smallest division is 5 mm. its length is about 3 metres. b. Solid Staff 2. It has a moving target against which readings are taken by the staff man. The sliding target comes along with the vernier. c. Telescopic Staff 3. The readings are always taken from the telescope hence appear inverted. Therefore, readings are taken from downwards. d. Target staff 4. It has three telescopic lengths of 1.5, 1.5, and 2 meters when stretched out fully. Normally, its total length is 5 metres

Match the following, in the context of the leveling staff. a. Self-reading staff 1. The smallest division is 5 mm. its length is about 3 metres. b. Solid Staff 2. It has a moving target against which readings are taken by the staff man. The sliding target comes along with the vernier. c. Telescopic Staff 3. The readings are always taken from the telescope hence appear inverted. Therefore, readings are taken from downwards. d. Target staff 4. It has three telescopic lengths of 1.5, 1.5, and 2 meters when stretched out fully. Normally, its total length is 5 metres Correct Answer <span style="background-color: rgb(255, 255, 255);">a - 3, b - 1, c - 4, d - 2</span>

Concept:

Leveling Staff:

• Along with a level, a leveling staff is also required for leveling.
• The leveling staff is a rectangular rod having graduations.
• The staff is provided with a metal shoe at its bottom to resist wear and tear. The foot of the shoe represents zero reading.

Leveling staff may be divided into two groups:

• Self-reading staff
• Target staff.

A. Self reading staff:

• This staff reading is directly read by the instrument man through a telescope.
• In a metric system staff, one-meter length is divided into 200 subdivisions, each of uniform thickness of 5 mm. All divisions are marked with black on a white background. Meters and decimetres are written in red colour.

The following three types of self-reading staff are available:

• Solid staff
• Folding staff
• Telescopic staff​

Solid staff:

• It is a single piece of 3 m.

Folding staff:

• A staff of two pieces each of 2 m which can be folded one over the other.

Telescopic staff:

• A staff of 3 pieces with upper one solid and lower two hollow. The upper part can slide into the central one and the central part can go into the lower part.
• Each length can be pulled up and held in position by means of a brass spring.
• The total length may be 4 m or 5 m.

B. Target staff:

• If the sighting distance is more, instrument man finds it difficult to read self-reading staff. In such a case, a target staff may be used.
• Target staff is similar to self-reading staff but provided with a movable target.
• Target is a circular or oval shape, painted red and white in alternate quadrants. It is fitted with an a vernier at the center.
• The instrument man directs the person holding the target staff to move the target, till its centre is in the horizontal line of sight.

Hence, the correct match of the leveling staff is as follows: