CONCLUDING REMARKS. 105 
the framing of such rules it will most likely become 
more and more obvious that they have been set 
down hastily, and under the guidance of only par- 
tial knowledge, that, in short, certain of these 
presumed laws of deposition and connexion are 
not unfrequently reversed by unqualified evidence 
in local investigations. ‘To carry with us precon- 
ceptions in investigating the geology of districts, 
implies error of the worst kind and greatest amount 
as their consequence. There can be no difficulty in 
admitting that Nature may have chosen to vary the 
detail of her plan of action in an infinity of ways 
during the gradual process of the construction of 
our earth in its different parts, and it should ever 
be remembered, that in proportion to existing 
complications of arrangement and number of 
substances in the first instance, will be the ratio 
of ee complications induced by succeeding 
revolutions. Experience of every passing day 
clearly shews us how greatly naturalists have been, 
-and still are stupified by preconceptions, and 
prepossessions of book learning. 
