xii 
PREFACE. 
templated. Indeed, Dr Leyden himself 
had actually undertaken one on a more ex- 
tended scale, embracing the whole continent. 
A small part was actually written, and is 
included in these volumes ; but his departure 
for India unfortunately prevented its com- 
pletion. In the present work, the object 
has been, not only to include the whole of 
Africa, but to trace the progress of discovery 
from the earliest ages. How far this difficult 
undertaking has been successfully perform- 
ed, must be left to the judgment of the 
reader. 
It was my original wish to have preserved 
the portion of the narrative composed by 
Dr Leyden, distinct from the additions 
made to it. On considering, however, the 
general enlargement which it was necessary 
to give to the work, it appeared that such 
a plan would have broke down entirely its 
unity and connection. It seemed of more 
importance to the public to receive a dis- 
tinctly arranged view of the subject, than to 
be able to distinguish, at a glance, the con- 
tributions of its respective authors. There 
appeared a necessity, therefore, for taking 
