XXI 



As I shall often be obliged to cite these 

 different works, I shall mention in notes 

 the abbreviations, which I have used to in- 

 dicate the titles. 



I. Astronomical observations, trigonome- 

 trical operations and barometrical measure- 

 ments made during the course of a journey 

 to the equinoctial regions of the New Con- 

 tinent * from 1799 to 1804. This work, 

 to which are added historical researches 

 on the position of several points important 

 to navigators, contains, first, the original ob- 

 servations which I made from the 12° of 

 southern, to the 41° of northern latitude; 

 the transits of the sun and stars over the 

 meridian; distances of the moon from the sun 

 and the stars ; occultations of the satellites ; 

 eclipses of the sun and moon ; transits of 

 mercury over the disk of the sun ; azimuths ; 



* Astron. Observations, two volumes in 4to. I 

 have discussed in the introduction, placed at the head 

 of this work, the choice of the most proper instru- 

 ments to employ in distant journies, the degree of pre- 

 cision that can be obtained in the different kinds of 

 observations, the peculiar motions of certain great 

 stars of the southern hemisphere, and several methods, 

 the use of which is not sufficiently common among 

 navigators. 



