INTRODUCTION. 
xxi 
ence of a Southern continent is neceffary to preferve an 
equilibrium between the two hemifpheres. But however 
plaufible 
done to find it. M. Le Monier has alfo two additional Memoirs on the fame fubjedt, in 
the volume for 1779, occafioned, as it appears, by fome objections 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 objections which have been made to M. Le Monier s hy- 
pothefis ; nor has he been particular enough in his two Memoirs, which reply to them, 
to enable me to fay of what importance the objections are. I can only gather, that they 
contain fome exceptions to the quantity by which M. Le Monier aflerts the variation al¬ 
ters in io° of longitude, under the parallel of 54 0 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 final! 
importance to geography ; as the moft ftrenuous aflerters of its exiftence 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, M. Le Monier has, and I am forry to obferve it, 
with fome afperity too, particularly in his fecond Memoir, endeavoured to cenfure the 
judgment and conduct 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 die motives which induced Captain Cook to place no de¬ 
pendence on the arguments, now adduced by M. Le Monier , in fupport of his fuppofition; 
and which, M. Le Monier mult know, were not unattended to, at that time, from what 
the Captain has faid, p. 236. Vol. IT. of his Account of the Voyage. And it may be 
proper to obferve here, that what fell from Captain Cook , on this fubjedt, was to fhew that 
this circumftance was then attended to, and not to throw blame on M. Bouvet , for whofe 
memory and abilities Captain Cook entertained great refpecl: nor is it incompatible with 
the utmoft refpecf, for a man to have a favourable opinion of his own labours ; or to en- — 
deavour to fhew why he thinks the difagreement between them and thofe of another per- 
fon, 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 fo harfhly, as he has 
done, in feveral parts of his fecond Memoir. 
The fubftance of M. Le Monier’ s argument is this. In 1739, when M. Bouvet’s dif- 
covery is fuppofed to have been made, the methods for determining the longitude of a 
{hip at fea were very defective ; and, of courfe, the longitude of any land which happened 
accidentally to be feen by one, was equally uncertain. On a prefumption that this was the 
cafe with refpecl to Cape Circumcifion, M. Le Monier enquires into the quantity of the 
variation of the magnetic needle, obferved by M. Bouvet at that place; and alfo into ob- 
fervations of the fame kind, made at other places in the neighbourhood of it, about the 
fame 
