As already remarked the formation we have described is that of almost the whole Red Sea, but south of Suakin it loses the regularity that is so noticeable northwards. The area marked on the map (p. 126) as “Suakin Archipelago” consists of innumerable small reefs, shoals and islets, the water between being of very irregular depth, three hundred fathoms being found close alongside surface reefs. Opposite Trinkitat the water shoals gradually, only 30 to 40 fathoms being found as far as 45 miles from land. The shore itself is extremely low and sandstone hills are absent. The area marked Shubuk, south of Suakin, shewn on the map enclosed by a thin semicircular line on the north and east sides and by the land on the west and south, has a very remarkable structure. An area of 100 square miles is enclosed by a regular and unbroken reef, indicated by the above curved line, the space within being a most intricate maze of reefs with comparatively deep canal-like passages between them. In the south are broader passages and some islets of elevated coral. The bounding reef is extremely regular and, on its eastern side, unbroken. It consists of a steep slope and precipice of growing coral up to near the surface, when the slope becomes very gradual and forms a nearly smooth surface of stunted corals with grey _Xenia_. This extends to among the breakers, above which is a band of gravel formed of broken and wave-rounded pieces of coral. Within is sand, and the coral capped sandbanks of the labyrinth. Landwards the ground is for miles so low and so much broken into by salt lagoons and marshes that a definite coast-line can scarcely be said to exist. This is the remains of an old delta of the Khor Baraka, a river which rises in the Abyssinian highlands, but which nowadays never reaches the sea. Its floods come down on to the maritime plain at Tokar, where, spreading over a considerable area, they render possible the growth of cotton and other crops in the fine soil they leave soaked with water. Tokar is thus the one fruitful spot of any size on the whole Red Sea coast, but its character of fertile oasis is but short-lived. When the crops are gathered even the dry cotton stalks must be removed lest they should collect the sand, which, every day of the summer, is carried over them by burning gales, and so would convert the fertile ground into barren sandhills. As it is, at any rate at present, impossible to predict these floods the seed must be sown after each, even though it frequently happens that another flood comes down and carries it all away. The seed must then be patiently re-sown, and that left by the last flood will grow and bear. In the old days, before man was there to make any use of it, the Baraka formed a regular delta, subject to yearly floods, a miniature Egypt. The growth of coral in this neighbourhood would then be impossible, the shifting sand, muddy and freshened water rendering its life impossible.