To draw the gores that compose the terrestrial globe, the mapmaker starts by drawing the line of the Equator, on which all the degrees of longitude are marked at equal intervals. Thirty-six intervals of 10° each form the entire circumference of the Earth. By convention, each gore is 30° wide and is bounded by two arcs of a circle with a radius equal to 270°. Inside each gore, the mapmaker draws two other arcs passing through the poles of the intermediate meridians. By dividing each arc into equal parts representing intervals of 10°, the mapmaker obtains a series of points that, once connected horizontally, make it possible to draw all the parallels. By transferring the geographic coordinates of places onto this cartographic grid, the mapmaker can draw the Earth's entire surface on a plane, which will assume a spherical shape only after attaching the gores to the surface of a globe.