to perceive ; the faint hope which I cherish of success rests 

 on the particular favour which my countrymen have long 

 bestowed on a small work which I published, soon after my 

 return from Mexico, under the title of Ansichten der Natur, 

 and which treated some portions of physical geography, such 

 as the physiognomy of plants, savannahs, deserts, and cata- 

 racts, under general points of view. Doubtless the effect 

 which this small volume produced was far more attributable 

 to its indirect action, in awakening the faculties of young 

 and susceptible minds endowed with imaginative power, than 

 to any thing which it could itself impart. In my present 

 work, as in the one to which I have just alluded, I have 

 endeavoured to shew practically, that a certain degree of 

 scientific accuracy in the treatment of natural facts is not 

 incompatible with animated and picturesque representation. 

 Public discourses or lectures have always appeared to me 

 well adapted to test the success or failure of an endeavour 

 to unite detached branches of a general subject in a sys- 

 tematic whole ; with this view a series of lectures on the 

 Physical Description of the Universe, as I had conceived it, 

 was delivered both in Berlin and in Paris, in German and 

 in French. These discourses were not committed to writ- 

 ing ; and even the notes preserved by the diligence of some 

 attentive auditors have remained unknown to me ; nor have 

 I chosen to have recourse to them in the execution of the 



