existing Physical Causes during stated Periods of Time. 27 
same extent, but that from time to g 
time new land would be formed by 
the elevatory movements of the sea- 
DUT 
3F 
bottom to compensate for what had se 8 y 
been carried into the ocean by the Sako 
continued operations of rivers and FBG 
breakers.* In speaking of the ele- Te § 
vation of the sea-level, I only refer . aes 
to the intervals between those move- gs 
ments of the land which might 8 
neutralize in an instant all that had 8 4 
been effected by the operation of 8 = 
rivers for immense periods of time. a ve 
_ It would add very much to the 
interest of this inquiry if any proof 
could be brought forward of a re- 
cent gradual upward movement of 
the sea-level. This would, how- 
ever, be difficult to observe,} on ac- 
uab o hg paruvduosow 
nas ay; uodn poogia ay2 ssardva of popuayu 
ru oo 82 asayy Bursoddns “was ay2 fo 
OL 9) yenba [aAa]-eas Jo ast oy} sejvatput (,2) oll] payjop [ejuOZHo0Y oYT, 
7 
La 

level, except just at the mouths of ese 
rivers, where the deposits of fluvia- a hay 
tile alluvium might raise the land 8 = § 
from time to time and keep it al- sss 
ways above the rising waters. Ses 
The deposits situated at a few sy 
such localities have been described SSS 
by the best observers, and [ hope to sq 
show that in several cases there are 2 Sq 
appearances which might be partly ess 
explained by changes of the sea~ & 22g 
evel, but that amuch greater num- % £38 
ber of cases and more certain evi- = ee: 
dence would be needed before such > wbay 
an event could be satisfactorily © iz? 
ved. I propose to make some J ond 
remarks upon this point, after hav- 3 = qd) 8538 
ing submitted the evidence which 3 . ae be 
has induced me to believe that the oF ae 
Supply of detritus under present — : = & a3 | 
* “Tt is not necessary that the present land - 4. 
should m away 1 ee a g as = 
Proportion as new land shall appear; or con-— eo 4 3 & 
versely, an equal proportion of new land S 38S 
be produced as the old is made to dis- 3 eis 
win Ss atene cee of the Earth, 1795, SF Ss 
{ See Darwin, in, Coral Reefs, &c., edit. 1851, a7 E 
Pp 

