SUBTERRANEAN MOVEMENTS, &c. Ill 
of dislocation to the elevated and depressed portions of the strata, or 
what is the relation of ‘hade and throw’ — and whether there be any 
connexion between the dip of strata and direction of hade and throw. 
(See Diag. No. 15.) 
First. — Relation of ‘ hade and throw.’ A general law of this relation 
has been long known to miners and colliers, to which in secondary 
strata few exceptions have been found. It may be thus expressed ; 
the ‘ slip,’ or plane of dislocation hades, dips, underlays, or is inclined 
to the vertical so as to pass under the depressed portion of the strata 
which are displaced. ( See Diag. No. 16. J 
Thus A is the downcast or depressed set of strata and B the upcast 
V. v. the plane of dislocation, inclined from v. v/ the vertical, so as 
to dip under the downcast side. The contrary case which in some 
hundred instances of dislocation, I have never seen , would be as in the 
next diagram (No. 17. j 
In mining language the beds are highest on the ledger (lower) side 
of the vein, and lowest on the hanger (upper) side. 
The hade of veins and faults varies in strata of different quality 
as limestone, sandstone, plate, &c„ for it is most nearly vertical in 
the hardest and most solid rock as limestone, hard gritstone, hut slopes 
most from the vertical (‘ hades most’) in plate and soft alternations. 
The width of the fissures varies in the same manner, being open 
in limestone, partially contracted in gritstone, but much reduced in 
breadth in plate. These are important facts. 
Secondly. Relation of the throw of veins to the dip of the strata. 
In particular districts the veins throw the beds up or down 
more in one direction than other, and there appears some law of the 
relation of dip and throw. Mr. Forster observes that the east and 
west veins of Weardale generally throw the north cheek up ; and 
