xxii INTRODUCTION. 



that its navigation was impeded by a cataract at no great 

 distance from its mouth ; but that was not considered as a 

 reason why it should not again become navigable beyond it. 

 Maxwell's information from the slave dealers stated it to be 

 so for six hundred miles above this cataract. 



In exploring the course of an unknown river upwards, 

 there would obviously be less risk to the parties employed 

 than in following the stream downwards. In the first case 

 a retreat could always be secured when the navigation 

 became no longer practicable, or the state of the coun- 

 try rendered it unsafe to proceed ; in the second, every 

 moment might be pregnant with unforeseen dangers from 

 which there could be no retreat. The river might, for in- 

 stance, suddenly and imperceptibly become bristled with 

 rocks, and its rapid stream roll with such velocity as to 

 sweep the unfortunate navigator to certain destruction down 

 a cataract ; or it might spread out its waters into a wide 

 lake without an outlet, which, becoming in the dry season 

 a boundless swamp, would equally doom him to inevitable 

 destruction No one can tell what the fate of Park may 

 have been, but no one will believe that this enterprising 

 traveller finished his career in the manner related by 

 Isaaco, on the pretended authority of Amadou Fatima. 

 Some persons indeed are still sanguine enough to suppose 

 he may be living. It is just possible, and barely so, after 

 such a lapse of time, that this unfortunate traveller may 

 have been hurried down the stream of the Niger into the 

 heart of Africa, and placed in a situation from whence 

 he had neither the means of returning or of proceeding ; 

 but what these obstacles may have been, whether moral or 

 physical, or both, in the total absence of all information 



