ABRIDGED NARRATIVE OF TRAVELS 



THROUGH THE 



INTERIOR OF SOUTH AMERICA, 



From the Shores of the Pacific Ocean to the Coafts of Brazil and Guyana, 



defcending the River of Amazons ; 



As read by Mr. De la Condamine, Member of the Academy of Sciences at Paris, at a Sitting of 



that Academy on the 28th April 1745. 



A T the clofe of March 1743, after a refidence of fix months in a defert, at Tarqui, 

 ^^-^ near Cuenca, in Peru, during which I had inceflkntly, night and day, to contend 

 with an atmofphere unfavourable to aftronomy, I learnt from Mr. Bouguer, then 

 near Quito, at the northern extremity of our meridian, that he had there made a 

 feries of obfervations of a ftar, intermediate between our two zeniths, of which obferva- 

 tions many were effe£led on the fame night : this ftar had been obferved by me at the 

 fouthern extremity of the line. By thefe fimultaneous obfervations, on the importance 

 of which I had laid much ftrefs, we attained the fingular advantage of being enabled 

 to afcertain precifely, and beyond difpute, the real amplitude of an arc of the meridian 

 of three degrees, the meafurement of which was known to us geometrically, and this 

 without having any thing to apprehend from variations, whether of an optical or a real 

 nature arifmg from the motion of the ftar, on account of its pofition having been fixed 

 at the fame inftant of time by the two obfervers at the oppofite extremities of the arc. 

 Mr. Bouguer, arriving in Europe fome months before me, communicated the refult at 

 the laft public meeting of the fociety, a refult correfponding with that of the operations 

 at the polar circle * ; as this, with that of the laft effe6ted in France t, all confpiring to 

 prove that the earth is a fpheroid flattened towards the poles. Taking our departure m 

 the month of April 1735, twelve months earlier than the academicians difpatched to 

 the north, we reached Europe, on our return, by feven years too late, to communicate 

 any thing new refpeding the figure of the earth. This fubjedt, fince then, has been 

 treated by fo many able hands, that I truft for excufe in referring to the memoirs of the 

 academy the detail of my individual obfervations on the matter, renouncing the privi- 

 lege, but too hardly earned, of addrefling this afl'embly on that head. 



Neither ftiall I enlarge here on other academical labours, either individually under- 

 taken, or in common, during our voyage from Europe to America, at the different 

 places of our fojourn after arriving in the province of Quito, and during the frequent 

 intervals occafioned by obftacles of every kind, which but too often delayed the pro- 

 grefs of our operations. To dilate on thefe, irrelative as they were to the meafurement 

 of the earth, would require extrads from a number of memoirs, which in the fpace of 



* Effefted by Meffrs. Maupertuis, Clairaut, Camus, and Monnier, of the Royal Parifian Academy, in 

 conjunAion with the Abbe Outhier, a correfpondent of that academy, and M. Celfius, aftronomical 

 profeffor at Upfal. 



t By Meffrs. Caffini de Thury and L'Abbe de la Caille. 



2 E 2 feven 



