HOW 2021 AGRICULTURAL NECO SPECIMENS WILL COME OUT
Proper Identification of the Specimens
All about specimen A-D
Specimen A-C are all Surveying Instruments
Specimen A – Measuring Tape
- It is usually made of linen or fine steel sheet.
- It is usually marked on one side with metric units and the other side with the imperial unit.
- The Measuring Tape is of various types and lengths.
- The Measuring Tape is normally wound in a small case from where it is unwound for use.
- It is used in taking short or detailed measurement of length, breath and height.
Specimen B – Gunter’s Chain
- It consists of a series of dumb bell shaped links of steel wires joined together by three small rings.
- One Gunter’s Chain is normally 20.13m (66ft) in length.
- It has brass handles at either side.
- It is divided into 100 links so that each link is 19.8cm or 7.92ins.
- A link is the distance from the middle of the central ring to the middle of the next central ring.
- The chain is entirely metallic.
- To serve as a distance measuring device used for land survey.
Specimen C – Ranging Pole
- Ranging Pole is made of wood or metal.
- It is of varying lengths e.g., 1.8m, 2.4m or 3.0m
- It is generally circular in section, through some octagonal types are obtainable.
- It is usually painted black, bright red and white to enable it to be seen from a distance.
- It has a pointed end.
- It is used for marking stations.
- It is also used for making straight lines.
Specimen D – Peg (Also know as Arrow or Pin)
- This is thin pointed steel wires of about 30cm long with one end curved into a ring.
- A red cloth is normally attached to the ring so that it can be seen from afar.
- It is used during chaining for marking off chain lengths as measured.
- It can also be used for marking stations.
Maintenance of those Surveying Instruments.
- They must be cleaned after use.
- Keep instruments in dry and cool places.
- Those metal parts should be oiled or greased or painted before they are put away for a long time.
- Replace worn-out parts.
- Keep instruments away from heat and rain to prevent damage and rusting respectively.
Take note of this