Weather map motion. Two-dimensional streamlines based on wind speeds at various levels show areas of convergence and divergence in the wind field, which are helpful in determining the location of features within the wind pattern. A popular type of surface weather map is the surface weather analysis, which plots isobars to depict areas of high pressure and low pressure. Cloud codes are translated into symbols and plotted on these maps along with other meteorological data that are included in synoptic reports sent by professionally trained observers. The use of weather charts in a modern sense began in the middle portion of the
What Is History? of things in the world, in a 1970 article entitled "Marxism and History", Carr argued that with the exception of the Mexican Revolution, every revolution in the last sixty-odd years had been led by Marxists. The other revolutions Carr counted were the revolutions in Cuba, China, Russia, and a half-revolution in Vietnam (presumably a reference to the then on-going Vietnam War). This together with what Carr saw as the miserable condition of the Third World, which comprised most of the world led Carr to argue that Marxism had the greatest appeal in the Third World, and was the most likely