THE FEESH-WATER LOCHS OP SCOTLAND. 



223 



The only extensive basin in the islands is the Harray basin, which 

 drains 60 square miles of conntry, and includes five lochs which were 

 surveyed. Lochs Hundland and Boardhouse are in one basin, the Muckle 

 and Peerie Waters in Rousay are in another ; all the other lochs drain 

 independently into the sea. The lochs surveyed thus fall into eight distinct 



IttUSAJTJ k. r^ , 



md^n'^^Sr^ 



-N^V 



^3 



Strorisay 

 Firth 



Engltsh Mi!e3 



I 2 3 4 5 15 



FIG. 24. INDEX MAP OF THE ORKNEY ISLANDS. 



basins. The shores of all the lochs slope at a very low angle, and are 

 paved with flat stones, so that approach to the shore in a boat was usually 

 difficult, except at spots artificially deepened. 



Though some of the lochs were partly overgrown with weeds, very 

 commonly the bottom was free from weeds, and could be seen in the 

 deepest parts. The paving of flat stones could be seen to continue all 



