1911 Encyclopædia Britannica/Crau

CRAU (from a Celtic root meaning “stone”), a region of southern France, comprised in the department of Bouches-du-Rhone, and bounded W. by the canal from Arles to Port du Bouc and the Rhone, N. by the chain of the Alpines separating it from an analogous region, the Petite Crau, E. by the hills around Salon and Istres, S. by the gulf of Fos, an inlet of the Mediterranean Sea. Covering an area of about 200 sq. m., the Crau is a low-lying, waterless plain, owing its formation to a sudden inundation, according to some authorities, of the Rhone and the Durance, according to others of the Durance alone. Its surface is formed chiefly of stones varying in size from an egg to a man’s head; these, mixed with a proportion of fine soil, overlie a subsoil formed of stones cemented into a hard mass by deposits of calcareous mud, beneath which lies a bed of loose stones, once the sea-bed. Naturally sterile and poor in lime, the Crau is adapted for agriculture by the process of warping, carried out by means of the Canal de Craponne, which dates from the middle of the 16th century; about one-quarter of the region in the north and east has thus been covered by the rich deposits of the waters of the Durance. The soil also responds in places to deep cultivation and the application of artificial manures. By these aids, uncultivated land, which before supplied only rough and scanty pasture for a few sheep, has been fitted for the growth of the vine, olive and other fruits; where irrigation is practicable, water-meadows have been formed. The dryness of the climate is unfavourable to the production of cereals.