In the early part of the 18th century another important event took place iu the history of English mining. The rich deposits of copper which have long constituted the principal mineral wealth of Cornwall, had up to this time been neglected, partly perhaps from this ore being confounded with " mundic; or worthless iron pyrites, common in most mines, and partly from its lying deeper in the veins than the ores of tin, which had always formed the chief object of search. When at length the nature and value of the Cornish copper ore was fully recog nised, a powerful stimulus was given to this new branch of-miuing, which has been carried on to the present time with great and increasing activity, the copper-mince of that county being now the deepest, the most extensive, and most productive in the world.
The great invention of the steam-engine, the progress of which during the hat century exercised such vast influence upon our arts and manufactures, was early rendered applicable to mining in this country, and in a great degree contributed to the present perfect state of the art. Savery, who, if we except the somewhat equivocal claims of the Marquis of Worcester to that honour, was the first person who con structed a practically useful engine worked by steam, sought in the first instance the patronage of persona interested in mines, as we ace by his publication entitled the ' Miner's Friend,' in which be describes the nature of his invention and its applicability to draining mines. At this period our mines, although comparatively shallow, were much inconvenienced by water, especially those which were not in situations where hydraulic machines could be employed, and hence the appli cation to them of this new power was at once obvious. The intro duction of Savery's engine into our mining districts probably led to the great improvements effected by Neweomen a resident in Devon shire, which vastly extended its utility, and indeed completely altered its principle. Their conjoined patent was taken out in 1705, and from that data the steam (or rather, atmospheric) engine became a most useful auxiliary in the hands of the miner, and was very generally employed for draining mines, not only in Cornwall, but hi the coal mines of Staffordshire and the north of England. The great improve ments introduced by Watt In 1765 and succeeding years were quickly appreciated by the mining interest, and his engines were speedily introduced into the mining districts of Cornwall, where they effected a grist saving of fuel, and therefore of expense, the coal used in that county being brought from South Wales. It is chiefly to the object of
economy that the efforts of late engineers have been directed, and so successfully, that their improvements have fully kept pace with the increasing depth of our mines, many of the most abundant of which would have long since been abandoned had not thia been the came. These great improvements have chiefly originated In Cornwall, where Ingenuity has been stimulated by the high price of coal ; and among the numerous Individuals who have contributed to them, tho names of Woolf, Trevithick, and Grose may be particularly mentioned.
The improvements In the manufacture of iron which took placo in the latter part of the last century, while they vastly increased the demand for it, and thus gave a great stimulus to the working of this metal, and of coal also for its reduction, contributed much to the perfection of mining generally, by enabling the miner to employ iron pumps instead of wooden ones, which were before used. This change allowed a better construction and arrangement of the pit-work, one of the most important appustue employed in mining, and hence greatei depths have been attainable than might otherwise have been the case Among many minor Improvements) which may be traced to the sum *urea may also be mentioned the laying -down of iron tram-roads underground in mines, as well as their use upon the surface : the arriage of the mineral to different parts of the works has thus been ;ready facilitated and economised.
with the improved machinery and apparatus intro luced towards the close of the last century, great improvements also ..00k place in the internal economy of mines and the arrangemcuts of he underground works. The ancient mode of following down the uro by irregular isolated excavations, and of stoping the bottoms of lie mines in the German manner, gave place to the present system of Laying open the ground for discovery and extraction, by a well-arranged series of shafts, levels, and winzcs. By this plan the ore or mineral is divided into more convenient masses for extraction, and can be worked much more economically than by the former mode of stoping or :tatting away the ground in the bottom of the levels, as still practised an the Continent.