XYIII -HOW CAN THE CULTIVATION OF THE OYSTER, ESPE- 

 CIALLY ON THE GERMAN COASTS, BE MADE PERMANENTLY 

 PROFITABLE r 



By Dr. Kakl Mobius. 



The first condition of successful oyster cultivation on our coasts is a 

 knowledge of the character of our natural oyster-beds. The majority 

 and the best of them are near the islands of Sylt, Amrum, and Fohr. 

 At the northern boundary of our oyster territory, near the island of 

 Eom, and at its southern boundary, near the islands of Pellworn and 

 Nordstrand, not far from the city of Husum, there are but few and 

 small beds. Farther south, near the mouths of the Eider and the Elbe, 

 there are none. 



As the oyster-beds share the character of that portion of the sea in 

 ■which they are located, it is necessary to cast a glance at the character 

 of the Schleswig-Holstein Archipelago. 



Compared with the open German Ocean it is a shallow sea. In the 

 whole southern portion of the open German Ocean between Germany, 

 Holland, and England the average depth varies from 35 to 45 meters. 

 In the Schleswig-Holstein Archipelago no such depth is found. The 

 greatest depth of the channels by which it is connected with the open 

 sea averages 15 to 20 meters. The bottom of the archipelago, therefore, 

 rises like a plateau above the deeper ground of the German Ocean. 

 The plateau is intersected by valleys of varying depth and breadth. 

 When the tide is in, the plateau is entirely covered with water, but 

 when the tide is out, large spaces are dry; and these are called 

 *' Watten,^^ from which this whole sea is also called the " Watte7i SeaP 



When the tide goes out, the water flows through these valleys 

 (called " deeps " by the sailors) both in a northerly and a southerly 

 direction into the open German Ocean, until the tide when it comes in, 

 which occurs twice a day from two sidys, makes the water flow back. 

 It rises and the valleys can no longer contain the water. It overflows 

 the banks and inundates the "TFa^fert"to such an extent that small 

 vessels can sail over the same place where a few hours ago men could 

 walk and drive wagons. For at high tide the water in the "TFatter* 

 /S'ea'- stands 6 feet higher in the north and 9 feet higher in the south 

 than when the tide is low. The current of the water is therefore in 



^Address made at the meeting of the German Fishery Association at Berlin, March 16, 

 1876, hy Dr. Karl Mohius, of Kiel. [From Circnlar No. 3 of the Deutsclie Fisclierei- 

 Verein, Berlin, March. 21, 1877.] Translated by Herman Jacobson. 



