xlvii 



the historical narrative: the second zoology 

 and comparative anatomy ; the third, the 

 political essay on the kingdom of New 

 Spain; the fourth, astronomy; the fifth, 

 physics and geology ; and the sixth, the 

 description of the new plants collected in 

 both Americas. The editors have dis- 

 played a liberal zeal to render these works 

 worthy of the public attention. I cannot 

 pass over in silence the frontispiece to this 

 itinerary. Mr. Gerard, with whom I have 

 had the pleasure of being acquainted these 

 fifteen years, has devoted to me some 

 moments of his time, and I feel the value 

 of this public testimony of his esteem and 

 friendship. 



I have carefully mentioned in this work 

 the persons, who have had the kindness to 

 communicate to me their observations ; 

 and in this introduction I ought to express 

 my gratitude to Messrs. Gay-Lussac, and 

 Arago, my fellow members of the Institute, 

 who have annexed their names to important 

 labours, and who are endowed with that 

 elevation of character, which is so congenial 

 to an ardent love of the sciences. Living 



