British Association for the Advancement of Science. 9 
of Mr. Snow Harris, though no doubt whatever was felt as to the 
answer which it would be proper to give to such an inquiry. The 
eflicacy of the protectors of Franklin in every possible situation, 
provided they be constructed upon proper principles, and mounted 
in a suitable manner, is now universally admitted. 
Mining.—Mr. Tarlor; jun., stated, that, in the course of his 
experience in practical mining, he had observed certain conditions 
necessary for the profitable working of metals. In the oldest, or 
scar limestone, he had observed that the miner was not remuner- 
ated ; but in newer lead measures he had a better chance of suc- 
cess, as in grits and shales. ‘The best chance was in altered rocks. 
In Cardiganshire he had observed a remarkable case ina slaty 
rock: where very schistose, the workings were poor; but where 
the rock was diced, as the workmen call it, they were certain to 
be rich: the strike of the altered rock being N. and S., and that 
of the veins E. and W. He had seen vainipicatid-caneie i the 
mechanical theory in North Carolina, especially in the rich veins 
of iron ore in that country. Mr. Sedgwick remarked, that fissures 
eaused by crystallization were, in general, very small; and that 
joints seldom coincided with rents ;—that in districts where gran- 
ite approaches slate rocks, we may be certain of finding the rich- 
est metalliferous deposits. 
Catastrophe in a Mine.—Mr. Sedgwick requested the attention 
of the meeting to an account, which he was about to submit, of 
the late unfortunate accident at the Workington Colleries. He 
pointed out, on the geological map, the rocks which occur in that 
neighborhood, and stated some of the phenomena of the stratifi- 
cation of the coal measures, which are there very much disturbed. 
There is an anticlinal line, on, the opposite sides of which the 
strata dip differently, so that, in one place, very important beds of 
coal crop out under the sea. Workings, quite submarine, have ac- 
cordingly been carried on for some time: in the Isabella pit, a 
depth of one hundred and thirty-five fathoms under high water 
has been reached. A culpable want of caution has been shown 
by the managers of late, as they have caused the workings to 
reach too near the sea—even within fourteen fathoms of it ; and 
the pillars and roof of the older works had been taken away, by 
which the danger was greatly increased. There had been re- 
peated warnings from the shrinking of the ground, and from an 
old work having become filled with water ;—also in the new 
Vor. XXXIV.—No. 1. 2 
