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 a Nation? French citizen has to have forgotten the massacre of Saint Bartholomew, or the massacre that took place in the South in the thirteenth century. While many nations, such as France, begin with a feudal regime such as a monarchy, others, such as the United States and Switzerland, are formed by acts of consensual aggregation. France and many others, however, survived their feudal roots while maintaining their identity. Renan inquires what is the organizing principle? It can't be race, because France is "Celt, Iberian, German...The most noble countries, England, France and Italy, are the ones where the blood is most mixed."