4 b siege of the south pole 
It began to be apparent that the approaches to the 
Antarctic circle were very effectively guarded. 
The next incident in Antarctic history is the dis- 
covery by the Spanish merchant ship Leon, returning 
from Chile in 1756, of a high mountainous land covered 
with snow in 55 0 S., and far to the east of Cape Horn. 
This was named San Pedro after the saint of the day, 
and though the longitude assigned by the discoverer is 
wrong by ten degrees, there is no reason to doubt that 
it was the island now known as South Georgia. 
The French natural philosophers of the middle of the 
eighteenth century, when passing in review the whole 
field of natural knowledge could not avoid so urgent 
a question as the nature of the unknown parts of the 
southern hemisphere. They did not lay stress on the 
popular idea that a great mass of land symmetrically ar- 
ranged round the south pole was necessary to maintain 
the equilibrium and uniform rotation of the Earth; but 
they showed a general tendency to believe in some such 
continent. Thus the celebrated mathematician Mauper- 
tuis, in writing to his patron, Frederick the Great, pointed 
out the vastness of the unknown area which contains 
room enough for a fifth part of the world larger than any 
of the others, and considered it unreasonable to suppose 
that no land existed there. He pointed out also that signs 
of land had been observed by Bouvet all along the edge 
of the ice. These lands must form as it were a world 
apart which if they could only be reached would furnish 
“ great opportunities for commerce and marvellous spec- 
tacles in Physics ” ; and he summed up by saying that 
he would rather have an hour’s conversation with a native 
of the Terra Australis Incognita than with the finest in- 
tellect in Europe. Maupertuis was too good a man of 
