INTRODUCTION. 



It has been urged, that the exigence of a Southern con- 

 tinent is necelfary to preferve an equilibrium between the 



two 



meridian of Greenwich : and confequently that this land may exift, notwithftanding 

 all that has yet been done to find it. M. Le Momerhzs alfo two additional Memoirs 

 on the fame fubjeft, in the volume for 1779, occafioned, as it appears, by feme ob- 

 jeftions which have been made to his former Memoir before the Academy. For fome 

 reafon or other, the Academy has not thought proper to print the objeaions which 

 have been made to M, Le Monief-'s hypothefis ; nor has he been particular enough in 

 his two Memoirs, which reply to them, to enable me to fay of what importance the 

 objedions are. I can only gather, that they contain fome exceptions to the quantity 

 by which M. Le Monicr aflerts the variation alters in 10° of longitude, under the 

 parallel of 54° South ; and which, I conceive, has little to do in the difpute. 



Whether the land, ufually called Cape Circumcifion, exifts or not, is a point of 

 fmall importance to geography ; as the mod ftrenuous a/Tcrters of its exiftcnce muft 

 allow it to be a very inconfiderable ifland, and of no ufe. This, therefore is not 

 in itfelf, a matter worthy of difpute : but, in afferting this, AI. Le Monur has and I 

 am forry to obferve it, with fome afperity too, particularly in his fecond Memoir 

 endeavoured to cenfure the judgment and condud of Captain Cook, whofe memory I 

 have every reafon to revere, as well as the judgment of thofe who were with him ■ 

 and, on this account, I cannot help feeling myfelf called on to explain the motives 

 •which induced Captain Cook to place no dependance on the arguments, now adduced 

 by M. Le Monier, in fupport of his fuppofition ; and which, M. Le Monicr muft 

 know, were not unattended to, at that time, from what the Captain has faid, p. 2 ''6. 

 Vol. II. of his Account of the Voyage. And it may be proper to obferve here that 

 ■what fell from Captain Cook, on this fubje£l, was to (hew that this circumftance was 

 then attended to, and not to throw blame on M. Boitvet, for whofe memory and 

 abilities Captain Cook entertained great refpedl : nor is it incompatible with the utmoft 

 refped, for a man to have a favourable opinion of his own labours; or to endeavour 

 to ftiew why he thinks the difagreement between them and thole of another perfon, 

 when there is one, does not arife from an error committed by himfelf. There could 

 therefore, be no occafion for M. Le Monier to exprefs himfelf as he has done in 

 feveral parts of his fecond Memoir. 



The fubftance o( M. Le Alonier's argument is this. In, 1739, when M. Botivet's 

 difcovery is fuppofed to have been made, the methods for determining the longitude 

 of a fliipat fea were very defedive ; and, of courfe, the longitude of any land wliich 

 happened accidentally to be feen by one, was equally uncertain. On a prefumption 

 that this was the cafe with refped to Cape Circumcifion, AL Le Monier enquires into 

 the quantity of the variation of the magnetic needle, obferved by M. Bouvet at tliat place, 

 and alfo into obfervations of the fame kind, made at other places in the neighbourhood 

 of it, about the fame time, as well as both before and fmce. And by comparing 

 thefe obfervations together, he concLudes, that at the time when Captain Cook waa 



km 



XXf 



