igi2. No. 14. THE HYDROGRAPHIC OBSERV'ATIONS. I5 



T/ic Reef, dividing the southern from the northern part of the 90-kilo- 

 metre long Foreland Sound, is situated at a distance of 60 kilometres from 

 the southern entrance of the sound, and 30 kilometres from its northern 

 entrance. The Reef was sounded out b}^ Hermansen on July 6, 1910. 

 It lies between Michael Sars Point, a sandy spit 4 kilometres in length, 

 covered with a lagoon, on the east side of the sound, and Murra}' Point, 

 a sandv tongue of land about i kilometre in length, also covered with 

 lagoons, on the west side. These sandy spits have been formed by the 

 tidal currents. The distance between the two points is 5^^ ■_. kilometres. 

 From them shallow sand-banks run out almost as continuations of the 

 points, but with a slight bend southwards on both sides, on the west side 

 as far as i kilometre, on the east side as far as 2 kilometres, both with 

 onl}' about i metre of water over them. The sand-banks continue from 

 both sides until the}- meet, their depths increasing to 4 metres at about 

 the middle of the channel. The Reef thus acquires the form of a curve, 

 with the convex side turned southwards. The deepest passage over the 

 Reef is about 500 metres in length and about half that in width. The 

 depths increase slowly on both sides out from the Reef, except on its 

 south side, west of the clearing mark shown on the map, where greater 

 depths are soon met with. 



Vessels drawing more than 3^ o metres should not go over the Reef. 

 The smallest depth on July 6 & 7, 1910, was 4^5 metres at low water 

 and 6^5 metres at high water, but in the spring, at springtide low water, 

 the depth will certainly not be more than 4 metres. The Reef should 

 preferably be passed with rising tide or at high water. The Fanii, which 

 generally drew 3^ 2 metres, could pass the Reef at any time. 



For clearing marks over the Reef see sketches A and B on the chart. 

 In sailing from the south over the Reef, a vessel should steer for Mt. 

 Laurantzon until in the line of clearing marks. 



On both sides of the Reef there are good anchorages to be found, 

 both on the east side and on the west. The current over the Reef has 

 a velocit}- of from 2 to 4 knots, the flood stream setting to the northward, 

 the ebb stream, to the southward. 



On the Muscovy Co.'s chart (1625) the Reef is called the Bar, on 

 that of Giles and Rep (about 17 10), 't RifF. 



The )io)ilicru part of Forelaud Sound, from the Reef to a line from 

 Vogel Hoek to Ouade Hoek, has a length of 26 kilometres. Its breadth 

 varies from 5 kilometres over the Reef to 18 kilometres between Richard 

 Lagoon and English Bay, then decreases to 13 kilometres, and increases 



