Not only cartographers and surveyors use a compass. This device is irreplaceable both for travelers, and for participants of competitions in sports orientation. Almost each person at least once holding a magnetic compass in hand asks a question: why his shooters have a red-blue coloring and who thought up such color scheme?
The main objective of a compass is the instruction on orient parts of the world: northern and southern. A red arrow of a compass, interacting with magnetic field of the earth, always points north, blue or black — on the contrary. Besides, the compass has a special scale by which it is possible to determine an azimuth and a corner of a deviation from a natural reference point. An interesting question — coloring of an arrow of a compass and its origin.
Origin of a compass
The first compass was built in China nearly two and a half thousand years ago and had an appearance of the spoon which is cut out from magnetite and carefully polished. It was established on ideally smooth board. The handle of this spoon indicated the southern direction therefore the first name of a compass is translated from Chinese as "knowing the South".
Followers of the Chinese scientists continued to design the models of magnetic compasses in which design there was always something the general: the arrow of the device, as a rule, represented a needle from the tempered iron. In ancient China, in the homeland of ferrous metallurgy, people knew that after heating and sharp cooling metal gains magnetic properties.
The first compasses had low accuracy: the error of indications was caused by high force friction force of the specifying part about the basis. This problem could be solved in two ways. On the one hand, to the shooter of a compass had in a vessel with water and fixed its center on a float that it could rotate freely. On the other hand, both ends of an arrow had to be ideally balanced, and the best way to reach it is to make them absolutely identical by the size and weight.
Traditions of the ancient people
Easily to distinguish the directions to which pointed a compass his shooters it was simpler to paint in different colors, than to do a different form. On a question of why the arrow of a compass is painted in red and blue color it is possible to find the answer in the annual calendar of ancient Assyrians. Traditionally, the North and the South at these people was called blue and red lands respectively. Therefore blue and red colors which had sufficient contrast were used as the main reference points for an ancient compass. With opening of the first permanent magnet of the name of poles and the color scheme for their designation were borrowed from a compass. The South Pole of a magnet was painted in red color, and northern — in blue. It is necessary to notice that the poles of the same name make a start from each other, and therefore the compass which arrow was made of the permanent magnet having a traditional coloring ceased to point north the blue party. Thus, the color circuitry of the instrument became completely opposite.
Arrow of a compass now
Compasses differ both in basic purpose, and on a color of arrows. For example, the bench and laboratory compasses applied at high schools point north a blue arrow. In the same time expensive navigation equipment has the red index of the northern direction. Still began very popular to do arrows figured, pointing only to a northern reference point. Anyway, before entrusting an unfamiliar compass navigation along a route, it it is necessary to check and study the instruction previously.