Value (degree) reduce areas on the map called the scale.
Such a reduction can be very large: ten, fifty, one hundred thousand times and more. So greatly reduce the image area on the map for it was convenient to use. One can not make a map, for example, the section from Moscow to St. Petersburg on a scale that reduces this terrain only two to ten times: the distance from Moscow to St. Petersburg more than 600 kilometers, even if it is reduced to one hundred times, then map, made on a sheet of paper that are longer than b km, will be completely useless — it can not be used. Yes, and this card will weigh about 18 tons, for paper — heavy stuff.
In such a large scale of one to a hundred, one in a thousand or one in five thousand, are only making special cards are very small terrain — building sites, fields, forests, parks, areas or small towns. They are called not maps, and plans terrain.
Accepted produce topographic maps on a scale:
1:10 000 (one in ten thousand),
1:25 000 (one to twenty five thousand)
1:50000 (one to fifty thousand)
1:100 000 (one thousand one hundred)
1:200,000 (one to two hundred thousand).
Scale Each card is most often expressed as a fraction whose numerator is always one, and the denominator — the number that indicates how many times the reduced image of the terrain on the map. Such form is called a numerical scale. With the denominator numerical scale of the map, we can always calculate the actual distance between any two points of the terrain. For example, if the map scale of 1:50 000, a ruler measuring the distance between any two points, we get a distance equal to 7 cm, then, knowing that the card reduced the whole area is fifty thousand times, we multiply 7 by 50 cm Ltd. and get 350 cm LTD (ie 3000 500 meters, or three and a half kilometers).
In addition to the numerical, the scale may have other views — verbal (natural) and linear (graphical) view. So, for example, scale 1:25 LLC can be expressed in words: one centimeter card contains twenty-five thousand centimeters location, scale 1:100 000 can be expressed as follows: one hundred thousand cards centimeter centimeter area.
However, since the surface of the earth is measured in such small quantities as centimeters (or even meters), uncomfortable, you should always be able to quickly transform the scale denominator in larger units — in miles. This is done simply: crossed out (mentally) in the denominator of the last two digits, we get the number of meters.
For example: 1:100 W
The denominator of the resulting number: one thousand meters. And if you cross out the three characters (for a total of five), we obtain the denominator the number of kilometers.
For example: 1:100 000 — turned one in the denominator kilometer.
Another example: 1:25 000 — in the denominator is nothing left, that is, zero kilometers. But there are still meters — 250. So, this scale in real terms (verbal) expression is read: one centimeter card corresponds to 250 meters on the ground.
The third type of scale — linear — is a straight line that is divided into several segments. Each segment concluded some round number of meters or kilometers area. The left-most section of the linear scale, in addition, is divided into fractional parts.
Linear scale on the map to determine the distance in a straight line between any two points of the route, even when you do not have any on hand measuring tools. To do this, you need to make
Linear (graphics) card has the fifty thousandth scale such form (Fig. 1) to two points on the map, between which you want to measure the distance, a narrow strip of paper and a pencil to make the finishing touches on it in front of the points. Then you have to put a strip of paper to the linear scale of the cards so that the first stroke was against a division of the right of the zero point and the left bar on the left would have been an interval scale from zero (Fig. 3). Against the right dash read the whole amount of kilometers (in this case — 4), and against the left dash can easily determine the share of kilometers and get the result — 4.6 km.