Exercise 17. Read and translate the text.

SURVEYING TECHNIQUES

Surveying or land surveying is the technique and science of determining the terrestrial or three-dimensional space position of points and the distance and angles between them. These points are usually on the surface of the Earth, and are often used to establish land maps and boundaries for ownership or governmental purposes. In order to accomplish their objective, surveyors use elements of geometry, engineering, trigonometry, mathematics, physics, and law.

Surveying has been an essential element in the development of the human environment since the beginning of recorded history (5000 years ago) and it is a requirement in the planning and execution of nearly every form of construction. Its most familiar modern uses are in the fields of transport, construction, mapping, and the definition of legal boundaries for land ownership.

Historically, distances were measured using a variety of means, such as chains with links of a known length, for instance a Gunter’s chain or measuring tapes made of steel. In order to measure horizontal distances, these chains or tapes would be pulled according to temperature to reduce sagging and slack. Additionally, attempts to hold the measuring instrument level would be made. In instances of measuring up a slope, the surveyor might have to “break” the measurement – that is, raise the rear part of the tape upward, plumb form where the last measurement ended.

Horizontal angles were measured using a compass which would provide a magnetic bearing from which deflections could be measured. This type of instrument was later improved with more carefully scribed discs providing better angular resolution, as well as through mounting telescopes with reticles for more precise sighting atop the disc. Additionally, levels and calibrated circles allowing measurement of vertical angles were added.

The simplest method for measuring height is with an altimeter – basically a barometer – using air pressure as an indication of height, but surveying requires greater precision. A variety of means, such as precise levels, have been developed to do this. Levels are calibrated to provide a precise plane from which differentials in height between the instrument and the point in question can be measured, typically through the use of a vertical measuring rod.

With the triangulation method, one first needs to know the horizontal distance to the object. The height of an object can be determined by measuring the angle between the horizontal plane and the line through that point at a known distance and the top of an object. In order to determine the height of a mountain, one should do this from the sea level, but here the distances can be too great and the mountain may not be visible. So it is done in steps, first determining the position of one point, then moving to that point and doing a relative measurement, and so on until the mountain top is reached.

Exercise 18. Read the text and mark the sentences as True or False:

1. Surveying or land surveying is the technique and science of determining the space position of points and the distance and angles between them.

2. In order to accomplish their objective, surveyors use elements of medicine and linguistics.

3. Distances were measured using a variety of means, for instance a Gunter’s chain or measuring tapes made of steel.

4. In instances of measuring up a slope, the surveyor might have to “raise” the measurement.

5. The simplest method for measuring height is with an altimeter – basically a barometer – using wind as an indication of height.

Exercise 19. Find the definitions of the following terms in the text and translate them into Russian. Make sentences using these words:

a) surveying;

b) chains;

c) a compass;

d) an altimeter;

e) a leveling instrument;

f) calibrated circles;

g) a triangulation method.

Exercise 20. Read the text about land surveying and fill in the necessary words and word-expressions from the box:

LAND SURVEYING

The aim of (1)………… is to re-establish and mark the corners of original land (2)……….. . The first stage is to research relevant records such as (3)………. (deeds), (4)……………. (marks on the ground) and any public or private records that provide relevant data. The job of a boundary surveyor retracing a deed or prior survey is to locate such monuments and verify their correct position. Over time, development, vandalism and acts of nature often (5)………….. on monuments, so the boundary surveyor is often forced to consider other evidence such as fence locations, (6)……………, monuments on the neighboring property, (7)………….. and other evidence.

Monuments are the marks on the grounds that define location. (8)……… are commonly used to mark boundary corners. Small pegs in the ground and steel rods are used as instrument locations and reference marks, commonly called (9)………. . Marks should be durable and long lasting, stable so the marks do not move over time, safe from disturbance and safe to work at. The aim is to provide sufficient marks so some marks will remain for future (10)…………….. of boundaries. Examples of typical man-made monuments are steel rods, pipes or bars with plastic, aluminum or (11)……….. containing descriptive markings and often bearing the license number of the surveyor responsible for the establishment of such. The material and marking used on monuments placed to mark boundary corners are often subject to state laws.

A total station or GPS (Global Positioning System) is set up over survey marks which were placed as part of a previous survey, or newly placed marks. The datum is established by measuring between points on a previous survey and a rotation is applied to orientate the new survey to correspond with the previous survey or a standard (12)………….. . The data are analyzed and comparisons are made with the existing records to determine evidence which can be used to establish boundary positions. The distance of lines between the boundary corners and total station positions are calculated and used to set out and mark the corners in the field. Checks are made by measuring directly between peg places using a (13)…………. . Subdivision of land generally requires that the external boundary is re-established and marked using pegs, and the new internal boundaries are then marked. A plat (survey plan) and description (depending on local and state requirements) are compiled, the final report is lodged with the appropriate government office (often required by law), and copies are provided to the client.

Many (14)…………… have considerable problems with regards to improper (15)……….., miscalculations in past surveys, titles, and others. Also many properties are created from multiple divisions of a larger piece over the course of years, and with every additional division the risk of miscalculation increases. The result can be (16)………. properties not coinciding with adjacent parcels, resulting in gaps and overlaps. The art comes in when a surveyor must solve a puzzle using pieces that do not exactly fit together. In these cases the solution is based upon the research of the surveyor, and following established procedures for resolving (17)…………... .

Exercise 21. Complete the sentences choosing the best variant according to the text “Land Surveying”:

1. A boundary surveyor’s job is

A. to mark the corners of the land boundaries desired by a customer.

B. to provide some relevant data.

C. to locate marks on the ground.

2. Pegs are used to

A. verify the boundaries.

B. locate boundaries.

C. make work safe.

3. To establish boundary positions

A. evidence of the existing records is used.

B. the distance between points on a previous survey is measured.

C. the global positioning system is set up.

4. Checks are made by

A. marking the corners in the field.

B. measuring the distance between pegs.

C. subdividing land.

5. Many properties have problems regarding

A. abutting them.

B. multiple divisions of a land piece.

C. improper calculations.

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