INTRODUCTION. Ixiii 



" when thefe voyages were firft undertaken. Both inftru- 

 " ments and obfervers, which deferved the name, were very 

 " rare ; and fo late as the year 1770, it was found necefTary, 

 " in the appendix to Meyer's Tables, pubHflied by the Board 

 " of Longitude, to ftate fadls, in contradidlion to the ailer- 

 *' tions of fo celebrated an aftronomer as the Abbe de la 

 « Caille, that the altitude of the fun at noon, the eafieft and 

 5' moft fimple of all obfervations, could not be taken with 

 *' certainty to a lefs quantity than five, fix, feven, or even 

 " eight minutes *. But thofe who will give themfelves the 

 " trouble to look into ihe ajlronomical obfervations, made in 

 *' Captain Cook's laft voyage, will find, that there were few, 

 " even of the petty officers, who could not obfcrve the 

 " diftance of the moon from the fun, or a flar, the moft de- 

 *' licate of all obfervations, with fufficient accuracy. It 

 " may be added, that the method of making and computing 

 " obfervations for finding the variation of the compafs, is 

 " better known, and more frequently pracflifed by thofe 

 •* who have been on thefe voyages, than by moft others. 

 " Nor is there, perhaps, a perfon who ranks as an officer, 



* The Abbe's words are, " Si ceux qui promettent una fi grande precifioii dans 

 " ces fortes de mcthodes, avoient navigue quelque temps, ils auroient vu fouvent, que 

 " dans I'obfervatioii la plus fimple de toutes, qui eft celle de la hauteur du foleil a ■ 

 " midi, deux obfervations, munis de bons qu.artiers de reflexion, bien rectifies, dif- ' 

 " ferent entr'eux, lorfqu'ils obfervent chacun a part, de 5', 6', 7', & 8'." 



Ephcmer. 1755—1765. Introduilian, p. 32. 



It mufl be, however, mentioned, in juftice to \1. de la Caille, that he attempted 

 to introduce the lunar method of difcovering the longitude, and propofed a plan of 

 Calculations of the moon's diftance from the fun and fixed ftars ; but through the 

 imperfedlion of his inftruments, his fuccefs was much lefs than that method was ca- 

 pable of affording. The bringing it into general ufe was referved for Dr. Mafkeljne, 

 our Aftronomer Royal. See the preface to the Tables for corre£iing ike EjfeSis of Re 

 fraillon and Parallax, publiflicd by the Board of Longitude, under the Direction of 

 Dr. Shepherd, Plumian Profeffor cf Aftronomy and Experimental Philofophy at Cam- 

 bridge, in 1772. - 



•' and 



