j S 6 NATURAL HISTORY 
depreflions, forafmuch as the lodes mud; owe their inclination to 
diftin<ft and pofteriour fubfidences produced by a caufe which we 
{ball by-and-by enquire into. Another reafon of fome irregulari- 
ties, is, that no fubfidence could equally affecft all the adjacent parts 
of fo mixed a mafs as the inteftines of the earth are, nor all parts 
moved fettle again in one dire&ion ; from the texture of the earth, 
I fay, it could not happen, but that the inclinations would be greater 
in one place than in another, nay fome quite contrary to others ; 
and the fa<ft is agreeable to the reafoning ; for we fometimes find 
two adjoining lodes of a quite oppofite inclination, viz. one under- 
lies to the fouth, as C D, Fig. iv. Plate XVII. the other, not 
twenty fathoms diftant, fhall underlye to the north, as Y Z, till 
both meet and unite at D, as in the mine called Huel-oules in St. 
Juft. Such lodes will fometimes crofs each other, as C, D, a , 
Y, D, Z, ibid. ( as they do at Bartifiy hill in St. Juft) plain evi- 
dences that they proceeded from fubfidences on the different fides 
of the lodes, viz. CD a from a fubfidence at a Z b, and Y D Z 
from a fubfidence at Z a c. Here is alfo plain evidence that thefe 
different fubfidences happened at different times, for one lode de- 
fends in full body through the other : when they crofs in fuch a 
manner, it is not eafy to decide which of the two lodes was firft 
formed. Mr. Hutchinfon, in his Trafts of the Cornifh lodes, page 
19 and 20, thinks that thefe lodes which crofs, (that is, run north 
and fouth) and run in full body through the main lodes, (which 
run eaft and weft) were formed after the main lodes, which, 
by cracking, gave way for the crofs-lodes to pafs through them, an 
ingenious fuppofition, and moft likely in general to be true ; but much 
will depend upon examining the inward ftrudture of thefe lodes ; if that 
ftrucfture is uniform throughout in each, and different from that of 
the other, then Mr. Hutchinfon’s folution is right, and that which 
is cracked muft have been prior to the other ; but if at the point 
of interfe&ion, D, both lodes have nearly an equal mixture of the 
fame feeders, ftone, clay, or ore, then were the fiffures inclined 
probably, and became replete at one and the fame time, and filled 
with one common matter. 
sect. ix. But that there have been different fubfidences, and at different 
Different fub- ^ eg w j}} ftm b e m0 re convincing, from another remarkable pofi- 
lidences prov- J r 1 
ed from frac- tion in which we fometimes nnd our Cormlh lodes. 
tared lodes. j n a m j ne called the North-Downs (a confiderable mine of tin 
and copper near Redruth) when they find the tin-lode quite worked 
out at the bottom, and no farther appearance of a lode, either 
dead or alive, (that is, impregnated or not) with or without walls; 
inftead of finking any farther, they drive acrofs, and at a fmall 
diftance 
