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Sprinkler Irrigation is a method of applying irrigation water which is similar to rainfall. Water is distributed through a system of pipes usually by pumping. It is then sprayed into the air and irrigated entire soil surface through spray heads so that it breaks up into small water drops which fall to the ground . Sprinklers provide efficient coverage for small to large areas and are suitable for use on all types of properties. It is also adaptable to nearly all irrigable soils since sprinklers are available in a wide range of discharge capacity.

Compass surveying is a branch of surveying in which directions of surveying lines are determined with a compass and the length of lines are measured with a tape or chain. In practice the compass is  generally used to run a traverse. In surveying, "Traverse" consists of a series of straight lines connected together to form a open or a closed polygon. Methods of traversing: Depending on the type of instrument used for the measurement of angles the method of Traversing can be classified as under; 1.Chain Traverse 2.Compass Traverse. 3.Plane Table Traverse. 4.Stadia Traverse. 5.Theodolite Traverse. IN Compass Traverse the direction of the traverse lines are determined with a magnetic compass. The magnetic Compass may be "SURVEYOR COMPASS" OR "PRISMATIC COMPASS" PRISMATIC COMPASS: The prismatic compass is one of the magnetic compass in which there is a prism for taking observations. The prismatic compass is generally smaller in size than a surveyor  compass. T

A contour is defined as an imaginary line of constant elevation on the ground surface. It can also be defined as the line of intersection of a level surface with the ground surface. For example, the line of intersection of the water surface of a still lake or pond with the surrounding ground represents a contour line.                                                                                                   It facilitates depiction of the relief of terrain in a two dimensional plan or map. The process of tracing contour lines on the surface of earth is called contouring. A contour map gives the idea of the altitudes of the surface features as well as their relative positions in a plan CONTOURING BY INDIRECT METHOD: The points surveyed are not necessarily on the contour lines but spot levels taken along with series of lines laid over the area. The position of spot levels is plotted on the plan and contours drawn by interpolation. BY SQUARES: In this method the whole area is div

Chain survey is the simplest method of surveying. In this survey only measurements are taken in the field, and the rest work, such as plotting calculation etc. are done in the office. This is most suitable adapted to small plane areas with very few details. If carefully done, it gives quite accurate results. The necessary requirements for field work are chain, tape, ranging rod, arrows and some time cross staff. Survey Station: Survey stations are of two kinds Main Stations Subsidiary or tie Main Stations: Main stations are the end of the lines, which command the boundaries of the survey, and the lines joining the main stations re called the main survey line or the chain lines. Subsidiary or the tie stations: Subsidiary or the tie stations are the point selected on the main survey lines, where it is necessary to locate the interior detail such as fences, hedges, building etc. Tie or subsidiary lines: A tie line joints two fixed points on the main survey lines. It helps to checking the

Plane table is a graphical method of surveying in which the field works and the plotting is done simultaneously. It is particularly adopting in small mapping. Plane table surveying is used for locating the field computation of area of field. Merits: It is most suitable for preparing small scale map or surveying small area. It is most rapid method. Field book is not necessary. No great skill is required for satisfactory map. It is particularly suitable for magnetic area where prismatic compass is not reliable. Contour and irregular object may be represented accurately. It is less costly. Demerits: Plane Table Essentially a tropical instruments. It is not suitable to work in wet climate. There are several accessories to be carried out and therefore they are likely to be lost. It is not suitable for accurate work. Parts of plane Table: Plane table essentially consist of Drawing board mounted on tripod. Alidade.

it is a measuring device used for land survey. Gunter divided the chain into 100 links, marked off into groups of 10 by brass rings which simplified intermediate measurement. On the face of it, the dimensions make no sense: Each link is 7.92 inches long; 10 links make slightly less than 6 feet 8 inches and a full length of 66 feet. In fact, he had made a brilliant synthesis of two incompatible systems, the traditional English land measurements, based on the number 4, and the newly introduced system of decimals based on the number 10.

A surveyor instrument having a short telescope fixed rigidtly to a horizontal rotating table.

A theodolite   is a precision instrument for measuring angles   in the horizontal and vertical planes. Theodolites are mainly used for  surveying  applications, and have been adapted for specialized purposes in fields like metrology . A modern theodolite consists of a movable telescope mounted within two perpendicular axes — the horizontal  or trunnion  axis , and the vertical axis. When the telescope is pointed at a target object, the angle of each of these axes can be measured with great precision, typically to seconds of arc.

work of  a surveyor consists of following three sections........ 1.field work. 2.office-work. 3.care and adjustment of instruments. 1.field-work:- this includes taking measurements for details, recording field-notes and setting of work. 2.office work:-it consists of preparing maps,plans and sections from the  data collected  in the field and also calculating areas and volumes and designing various structures. 3.care and adjustment of instrument:- a surveyor must be thoroughly  familiar with the instrument.He must knows the appropriate method of using instrument because even a minor injury to instrument is liable to make them out of order.

Surveying techniques have existed throughout much of recorded history. Under the Romans, land surveyors were established as a profession, and they established the basic measurements under which the Roman Empire was divided,  such as a tax register of conquered lands (300 AD). In the 18th century in Europe triangulation was used to build a hierarchy of networks to allow point positioning within a country. Highest in the hierarchy were triangulation networks. These were densified into networks of traverses  (polygons), into which local mapping surveying measurements, usually with measuring tape, corner prism and the familiar red and white poles, are tied.

The  following two basic principles should be considered while determining relative position of points on the surface of earth:- 1. determining suitable method for locating a point:- it is  always practicable to select two points in the field to measure the distance between them. These can be represented on paper by two points placed in a convenient positions. 2.working from whole to the part:- in surveying an area, it is essential to establish first of all a system of control points with great precision. Minor control points can then be established by less precise method and the details can be located  afterwards by method of triangulation or traversing between control points.  Know the basic and you will never need to know again and again.

测量 是 确定 物体 的相对位置 earth.Surveying 或 土地测量 表面 上 的 艺术 ，是 技术， 专业和 科学 准确地确定 点 和 them.Surveying 之间 的距离和 角度 的 地面 或 三维位置 一直 以来 有记载的历史 （ 5000年前 ） 开始 在 人类生存环境的 的 发展 的 基本要素 。 这是 需要 在规划 和 执行 几乎所有的 建筑形式 的 ..

IT  is a branch of survey which helps in determination of elevation of a given point or object with espect to some specified point or object. . Common levelling instruments include the spirit level , the dumpy level , the digital level, and the laser level. The dumpy level is an older style of optical instrument. It is commonly believed that dumpy levelling is less accurate than other types of levelling, but such is not the case. Dumpy levelling requires shorter and therefore more numerous sights,   but this fault is compensated by the practice of making foresights and backsights equal.

there are two main types of survey. 1.plane survey. 2.Geodetic survey. Plane survey:-I n plane survey the surface of earth assume as plane or straight its uses as limited distance. Geodetic survey:- in geodetic survey surface of earth assume as curve its use in long distance.

surveying  is the art of determining the relative positions of objects on the surface of earth. Surveying  or land surveying is the technique, profession and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them. Surveying has been an essential element in the development of the human environment since the beginning of recorded history (about 5,000 years ago). It is required in the planning and execution of nearly every form of construction..