II. Give English equivalents:

Вимірювальна рулетка (стрічка), горизонтальна відстань, туго натягнутий, зменшити провисання, вимірювальний інструмент, задня частина, останнє вимірювання, горизонтальний кут, магнітний азимут, кутовий дозвіл, більш точний, найпростіший метод, повітряний тиск, точний горизонт, вертикальна вимірювальна рейка, зйомка площини, електронний вимірювальний пристрій, сучасна найновіша сукупна станція, координати точок, супутникова система позиціонування, додаткові працівники, записувати данні

III. Read and translate the text: Surveying Techniques

Historically, distances were measured using a variety of means, such as chains with links of a known length, for instance measuring tapes made of steel or invar. In order to measure horizontal distances, these chains or tapes would be pulled taut 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" (break chain) the measurement - that is, raise the rear part of the tape upward, plumb from where the last measurement ended.

Historically, 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 upon, through 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 for surveying more precision is needed. Toward this end, a variety of means, such as precise levels, have been developed. 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.

As late as the 1990s the basic tools used in planar surveying were a tape measure for determining shorter distances, a level for determine height or elevation differences, and a theodolite, set on a tripod, with which one can measure angles (horizontal and vertical), combined with triangulation. Starting from a benchmark, a position with known location and elevation, the distance and angles to the unknown point are measured. A more modern instrument is a total station, which is a theodolite with an electronic distance measurement device (EDM) and can also be used for leveling when set to the horizontal plane. Since their introduction, total stations have made the technological shift from being optical-mechanical devices to being fully electronic with an onboard computer and software. Modern top-of-the-line total stations no longer require a reflector or prism (used to return the light pulses used for distancing) to return distance measurements, are fully robotic, and can even e-mail point data to the office computer and connect to satellite positioning systems, such as a Global Positioning System (GPS). Though GPS systems have increased the speed of surveying, they are still only accurate to about 20 mm. As well GPS systems do not work in areas with dense tree cover. It is because of this that total stations have not completely phased out earlier instruments. Robotics allows surveyors to gather precise measurements without extra workers to look through and turn the telescope or record data. A faster way to measure (no obstacles) is with a helicopter with laser echolocation, combined with GPS to determine the height of the helicopter. To increase precision, beacons are placed on the ground (about 20 km apart). This method reaches a precision of about 5 mm.

ІV. Answer the following questions:

1. How were distances measured?

2. Why were chains with links pulled taut?

3. What was the problem in measuring up a slope?

4. How were horizontal angles measured?

5. What was the improvement in a compass?

6. What were added to measure vertical angles?

7. What is the simplest method for measuring height?

8. What were the basic tools used in planar surveying?

9. What is a more modern instrument which can also be used for leveling when set to the horizontal plane?

10. What is EDM?

11. What is GPS?

12. Where does not GPS system work?

13. What is a faster way in measuring?