i88i.] 
A Geological Idea of Lord Bacon's. 
583 
Diemen’s Land in the south, New Guinea in the north, and 
New Zealand in the east (the latter by reaction from Africa), 
and of smaller islands, shows distinctly how land moved 
north has been by tertiary reaction cut off from the main 
section or continent, and how interference folds have been 
formed in the intervals through pressure from the north. 
When we start from Pr at the equator, and the north 
shore of South America at its east, and proceed over Pn on 
the same circle to Ap, we find at its east an island wave 
which extends and points south io° 44' at South America, 
extends and points to io° 44’ north, whose organisms present 
the characteristics of the Asiatic, northern section, and which 
separates from the southern section New Guinea and smaller 
islands whose organisms present either the Australian cha- 
racteristics or a compound nature. 
When we return over Ps, back to Pr and beyond, we find 
io° 44' north of the shore of South America the tertiary 
wave, Trinidad, Cuba, Yucatan, closing the circuit, — a wave 
which, with the supplementary isthmus south, is equal to all 
non-Australian land between the equator and continental 
Australia, and which, adding the volcanic south of Mexico, 
is equal to all land between the equator and Australia 
proper. 
Segment Ap is divided not in four, but in two parts, in 
proportion 1 : ( ^2*83) 3 = 1 : 4*78. 
The middle segment is divided north to south 1 : 2*83 : it 
reverses, closing the circuit, the relation of the hemispheres. 
Subsections, and the contiguity of the north section with 
Ap, are here extensively to be considered. 
The east limit of segment Ap, between the two continental 
sections, is like at Pr from South Carpentaria, 46° 56' ; the 
west limit, south of Sumatra to Australia, 23 0 28'. The east 
limit of the segment, north to the meridian dividing Af, is 
66° 32'. 
Ap stretches io° 44' into the arCtic circle, and measures 
from Lunk Leylon to the north or meridian Ap 66° 32'. 
The axis through the middle of the southern section of Af, 
on the meridian dividing all land and sea equally, is 66° 32'; 
that through the north section is 23° 28', plus 3 0 52' in the 
arCtic circle occupied by the coincidence of Af with Ap. 
The readers of Mr. Russel Wallace’s “ Island Life ” may 
observe the relation between my sections and the distribution 
of organisms. This relation becomes still more striking 
when subsections and the lines of intensity are considered. 
There exists an intimate relation between the distribution of 
gravity, and of consequent motions and oscillations of sea 
