224 DAHLAK 



had passed from the Mediterranean into the Red Sea and 

 vice versa.) 



The length of the Red Sea from Suez to the Straits of Bab 

 el Mandeb is 1,386 miles and its maximum width at the 

 level of Massawa is 207 miles. Its average depth is estimated 

 at 1,600 feet and the maximum at 7,780 feet at about the 

 centre of the sea near the 21st parallel, a little north .of Port 

 Sudan. The bar that rises just inside the Straits of Bab el 

 Mandeb lies at an average depth of under i ,000 feet. 



Between May and October the temperature of the air is 

 never below 86° F and the humidity of the atmosphere is 

 sometim.es more than 80%. Because of this high temperature 

 and heavy evaporation, constantly flowing rivers do not 

 exist and the salinity of the sea is more than 40 per 1,000. 

 The African and Arabian coasts are rocky in parts, but they 

 are generally defined by sand- and coral-banks protected by 

 reefs that follow the coastline. 



There are several islands of various size. These are mainly 

 of madreporic origin and form the archipelagos of Suakin, 

 Dahlak, Hanish and Farman, to mention the most important. 

 Only the axial zone which is free from islands, rocks and 

 banks offers a safe route for shipping. 



The archipelago of Dahlak lies between latitudes 15° 30' N 

 and 16° 37' N. It includes 126 islands, generally flat with 

 highly splintered coasts, lying on a foundation of neogenic 

 limestone, chalk and marl and containing calcareous corals 

 of the Pleistocene period. The Dahlak islands lie opposite 

 Massawa, but are separated by a wide channel from the 

 port, which can be approached by shipping from either the 

 north or the south. 



The temperature of this zone is very high and rain falls so 

 rarely that, apart from the growth of mangroves in a few 

 coastal areas, the vegetation is limited to a few miserable 



