358 
TlfE GKOLOOIST. 
having, in nearly all cases, been attended with most important re- 
sults, both as respects the quantity, as well as the kind of ore met 
with. Nevertheless, I am not aware of their having ever received 
any particular attention from geologists, nor of their liaving been 
anywhere described, circumstances which may pi'obably arise from 
the fact of these beds only being visible below the surface, and 
nsvially in deep mines ; or they may have remained unnoticed, from 
the really small amount of scientitic obsei'vation which in this country 
has been brought to bear on the facts connected with metalliferous 
deposits, compared with what has been done, and is still doing, in 
other branches of physical geology. The present article is drawn 
from memoranda made during several careful surveys of mines which 
arc notable, in North Stafibrdshire, for exhibiting the phenomena of 
the saddles in great force. 
Lign. 1. — Contorted or plicated strata seen in vortical section. 
The term metalliferous saddle, or rather simply " saddle," as used 
by the Derbyshire miner, is a very expressive one, and pictures, 
almost without the necessity of further description, the particular 
kind of structu.re to which it is applied. It will, however, assist us 
subsequently in more ways than one if we here recall a few of the 
facts connected with contorted strata so called, and which are so fre- 
quently to be observed in various rocks in nature . First then, in 
many localities, where good cliff-sections are exposed, the strata of 
various common rocks, and particularly schists and shales, are seen 
to have been crumpled, so to speak, or in other words, the beds, instead 
of continuing on with their usual regularity, become twisted and 
folded into the most sing-ularly complex forms, this kind of structure 
