If you are going on an interesting trip or just looking at maps on the Internet, everyone is faced with such a thing as scale. However, not everyone knows what it is, what kinds of scales exist and how to calculate it correctly.
What is scale
The word "scale" came to the Russian language from the language of accuracy - German - and literally translates as a stick for measurement. However, in cartography, this term refers to the number of times a given map or other image is reduced in comparison with the original. The scale is present on each map, and is also an integral part of any drawing.
What is the scale for?
So why do people need scale in practice? What does scale show? In fact, this concept is connected practically and theoretically with many industries: mathematics, architecture, modeling and, of course, cartography. Indeed, it is impossible to display a geographic object in its real size on any map, even an ultra-modern digital one. Therefore, when applying the image of certain cities, rivers, mountains or even entire continents to the map, all these objects are proportionally reduced. And how many times this is done, and is the scale that is indicated on the margins of the map.
In the old days, when cartography had not yet been applied to scale, but to depict the depicted objects at its discretion, the maps received were very inaccurate and were, rather, approximate. So travelers using them often got into trouble. Who knows, maybe the map used by Christopher Columbus also had the wrong scale, and so instead of India, he sailed to America?
Another industry that simply cannot exist without the use of scale is modeling. Indeed, when creating a drawing of a future building or aircraft, an engineer does this on a certain scale, reducing or enlarging the image depending on the need. So not one, even the smallest detail, can be made without using a drawing, and not a single drawing can do without scale.
The main types of scales
Despite the simplicity of the concept of "scale", there are several types. On maps, it is usually indicated either by numbers (numerical) or graphically. Graphic scales are divided into two subspecies: a linear view of the scale and transverse.
There are also subspecies of scale that are more relevant to map types. Depending on the size of the scales, maps are distinguished:
- Large-scale - from one to two hundred thousand or less.
- Medium-sized - from one in a million to one in two hundred thousand.
- Small-scale - up to one in a million.
Naturally, on small-scale maps some details are not applied, at the same time, large-scale maps may contain street names and even small lanes. In modern electronic cards, the user can adjust the scale himself, turning the card from a small-scale to a large-scale one in an instant, and vice versa.
Numerical and named scale
Scale data can be provided in a variety of ways. If on a map or drawing the scale is indicated using a fraction (1: 200, 1:20 000 and the like), then such a view is called numerical. When calculating this size, it is worth taking into account the fact that the scale with the number in the denominator is smaller. In other words, objects on a map with a scale of 1: 200 will be larger than on a map with a scale of 1:20 000.
The named scale indicates not only the size of the image reduction, but also indicates the units of measure by which this is done.For example, on a terrain plan it is indicated that 1 centimeter on it is equal to 1 meter. Named scale is rarely used for small-scale maps, and indeed for maps in general. It is more practical for various drawings. Especially if it is a tiny detail or, conversely, a huge residential complex.
Graphic scale
Graphic types of scales, as mentioned above, are of two options.
Linear is a scale depicted as an evenly-divided two-color ruler. As a rule, it is used on large-scale plans of the area and makes it possible to measure the distance on it using a paper strip or compass. This graphic scale option can help you find out the length of rivers, roads, and other curved lines.
Cross - an improved version of the linear scale. Its purpose is to determine the maximum distance indicated on the plan. A similar graphical option is usually used on specialized cards.
Scale of drawings
Having considered the most common types of scales in cartography, it is worth mentioning that this concept is also inextricably linked with drawing and architectural graphics. Whether it is engineering drawings of tiny mechanical parts or, conversely, drawings of huge architectural ensembles, in any case, the specialized scale of the drawings applies to them. Each drawing form has a column in which the scale of the designed product is indicated without fail.
It is noteworthy that even if the engineer creates a full-size drawing of the part, the scale 1: 1 is still indicated in the information about it. Unlike maps, in the drawings the scale can be not only reduced (1: 5), but also enlarged (5: 1) if the displayed product is of tiny size.
Today, only narrow specialists need the ability to correctly calculate the scale without the help of machines. Thanks to modern programs and instruments, other people no longer need to be well versed in the scale of a particular map - the computer will do everything for them. But still, everyone should have at least a rough idea of what the scale shows, how to calculate it correctly and what types of it exist - after all, it is a component of elementary literacy and human culture.