The sign of this subject is for most children who grew up in the USSR. On the lucky owner of a transparent strip with many holes in the form of various geometric figures, classmates glanced with envy. Nowadays this object is rather a rarity. Even the military itself is less likely to resort to the use of paper cards.
A bit of history
The exact time when people began to use the ruler is unknown, but archaeologists found flat wooden planks with divisions when excavated under the layers of sand and stone of settlements of ancient Hellenes. This is not surprising, because the architectural monuments of that era are impressive. The ancient designers who created these structures, for certain during the development of projects used some or other drawing tools.
A ruler with modern measures of length appeared in France. One day, people were sick of endlessly translating one measure of length into another (pounds, inches, arshins, elbows, etc.) and a meter was taken as a measure of length - one forty million from the circumference of the globe.
Well, like any human invention, the ruler, having appeared on the light, quickly began to develop. What kind of line does not exist. The usual strip with divisions. A ruler in the form of a gon with different angles. The usual protractor irreplaceable in drawing is a semicircle with divisions per degree, etc.
Why did the officers need a ruler
Military, planning their actions, from time immemorial used maps. And if the commanders of antiquity had no questions about how to place the location of their troops and enemy forces on the layout of the territory, then at a time close to modern times everything became not so simple.
The success of the planned offensive often depended on the rigorous execution by the subordinate units of a specific task in the established place and at a given time. Not the least role in this played maps of the terrain, which were the commanders. They placed the location of the parts, the direction of strikes and counterblows, the location of the fortifications.
The troops long ago ceased to consist only of cavalry and infantry. On the map it was necessary to designate machine-gun nests, location of communications equipment, gun calculations, positions of military equipment and much more.
It is because of the variety of symbols and signs applied to military topographic maps, and it became necessary to unify all these designations. The goal is to make a map developed by one officer, understandable and "readable" for all his other colleagues on shoulder straps. The standard officer's line was widely used during the First World War, with all the opposing sides at once.
What is an officer line
Probably everyone knows what this drawing tool looks like. Officer's line is rather a kind of stencil, with which you can put special signs on paper. For the convenience of use, it is usually made of some transparent material. The officer's line of the USSR was made of transparent celluloid. The material was not entirely transparent, but had a yellowish gray color. The modern Russian army uses an officer line, cast from solid transparent plastic.
Fans of antiques appreciate the Soviet option. But not only collectors are drawn to the old days. Officers, who still have to use a ruler, oddly enough, prefer "Made in the USSR" as well. The fact is that the officer's line, made of celluloid, practically does not break, unlike a modern colleague.
The officer line is not 100% universal. Some armies had separate views. Here, for example, the standard officer line. Photos from the standard set of officer's tablet.
Not much different and the next option. This is a naval officer line. Cadets of military schools also had their own line.
And here is another officer's line. Photo from the US Army equipment.
And such lines were found among the captured or killed German officers during the Great Patriotic War.
How it is used
Any of the listed types of rulers contains a set of all sorts of icons, which the military are supposed to designate certain tactical units. It is enough to put the ruler, press and circle the desired figure with a pencil. A whole set of all kinds of symbols and various figures (contours of flying machines, ships, other units of technology) contains any officer line.
Scale windows are designed so that, without wasting precious time on computing, estimate the distance on the map in real units. All other possibilities of the standard line No. 2 are the same as for any other drawing tool. The individual edges of the officer's line are made in the form of irregularities in various configurations. With their help, wavy lines are drawn on the map. Practically on all rulers there is a habitual protractor - a measuring device of corners.
Some specimens have a section in the form of a magnifying glass, with which you can make out small symbols and inscriptions on the map.
More difficult to use the line of specialized. For example, an artillery officer line. This is a whole measuring device with which the gunner could calculate, in addition to the range of fire, certain parameters of the ballistic trajectory, the sector of fire, etc.