NG. 



mineral and metallic substances found in the earth's crust. These substances are yariously 

 worked in a few localities; while the ores of silver, though less common, afford a larger source 

 ith earthy and other substances. Of the other useful metallic ores, lead, copper, tin, and zinc, 

 such great demand or generally applicable as the former. The metallic and other substances 

 , are found in regular beds, interstratified with the rocks in which they are imbedded; veins 

 its occur in veins or lodes which are not parallel to the stratification, but run in a direction 

 ocks, which have been produced by contraction or mechanical force after the deposition and 

 ns is very irregular, and of more or less limited extent; the vein is rarely if ever filled entirely 

 mineral is associated, and which occurs sometimes in such small quantities as not to be worth 

 to a great depth, as in Cornwall, where some of the mines are worked upwards of 1,000 to 



;he coal measures ; but iron is also extensively worked from a species of haematite, which is 

 ts of Corn wall,' is more abundant and characteristic of the carboniferous strata of Derbyshire, 



and is the level by which 

 the mine is drained. The 

 cross cuts are passages driven 

 from the shafts to the lodes 

 for the purpose of exploring 

 it, and which, when favor- 

 able Indications of ore are 

 presented, are extended on 

 the course of the lode, and 

 form .levels. The levels are 

 three feet wide and six feet 

 in height, are about ten 

 fathoms apart from each 

 other in depth, and by 

 means of which the opera- 

 tions of the mine are carried 

 en, and the ore brought to 

 the principal shafts. The 

 portions of the veins be- 

 tween the levels are called 

 pitches. Winzes are small 

 shafts extending from one 

 level to another. The cheeks 

 or walls, called roof and 

 floor, are definite partings 

 which enclose the lode, or 

 hanging wall; and foot watt, 

 if the lode has considerable 

 inclination. The outcrop is 

 where the vein reaches the 

 surface. 



SUMMARY OF THE MINERAL PRODUCE OF 



THE UNITED KINGDOM IN 1854. 



From the Mining Records. 



Quantity.. Value. 



Silver 700,000 oz. 192,500 



Coal 64,661,401 tons. 14,975,000 



Iron 3,069,838 9,500,000 



Copper 13,042 1,229,807 



Lead 64,005 1,472,115 



Tin 5,763 690,000 



Zinc 16,500 



Other Metals 500,000 



Total Value 28,575,922 



IEYNOLDS, 174, STRAND. 



