PBEFACE. 



The expedition of which an account is given in the fol- 

 lowing pages was undertaken in the year 1871, and it 

 was originally intended that a narrative of the proceedings 

 should be given to the public soon after our return to 

 England. Sir Joseph D. Hooker, who made careful notes 

 throughout the journey, hoped to complete the work 

 without much delay, and actually wrote the greater part 

 of the first two chapters ; but the constant demands upon 

 his time arising from his official duties at Kew, and the 

 important botanical works to which he is a chief con- 

 tributor, further increased by his election, in 1873, to the 

 Presidency of the Eoyal Society, so far interfered with the 

 completion of the original design as to compel him to re- 

 quest his fellow-traveller, Mr. Ball, to undertake the com- 

 pletion of the work. The latter was at the time engaged 

 in preparing for publication a memoir on the Flora 

 of Marocco, which has since appeared in the Journal of 

 the Linnaean Society, wherein the botanical collections 

 made during the journey are enumerated and described ; 

 and bis performance of the task allotted to him has been 

 further delayed by several prolonged absences from 

 England. 



As regards many countries visited by travellers a delay 

 of several years in publication might seriously affect the 



