Horn of Africa Consequently, they lose their moisture before reaching Djibouti and Somalia, with the result that most of the Horn receives little rainfall during the monsoon season. In the mountains of Ethiopia, many areas receive over 2,000 mm (80 in) per year, and even Asmara receives an average of 570 mm (23 in). This rainfall is the sole source of water for many areas outside Ethiopia, including Egypt. In the winter, the northeasterly trade winds do not provide any moisture except in mountainous areas of northern Somalia, where rainfall in late autumn can produce annual totals as high as 500 mm (20
German horn excessive. Although the French firm Jérôme Thibouville-Lamy in about 1928 introduced a piston-valved double-horn with ascending third valve, designed in collaboration with the horn player Louis Vuillermoz, the double horn has continued to be identified mainly as a German horn. The double horn essentially combines two instruments into a single frame: one horn in F, and a second, higher horn keyed in B. Like the single horn it has three valves, but each has a double set of tubing, the first tuned in F and a shorter set in B. By depressing a fourth valve (usually operated by the thumb),