ANNOTATIONS AND ADDITIONS. 



143 



( 21 ) p. 11. "A connected Sea of Sand." 



As the Heaths formed of socially growing Ericeee, which 

 stretch from the mouth of the Scheldt to that of the Elbe 

 and from the point of Jutland to the Harz, may be regarded 

 as one connected tract of vegetation, so the seas of sand 

 may be traced through Africa and Asia, from Cape Blanco 

 to beyond the Indus, or through an extent of 5600 geo- 

 graphical miles. Herodotus's Sandy Eegion interrupted 

 by Oases, called by the Arabs the Desert of Sahara, 

 traverses almost the whole of Africa, which it intersects 



