370 Mr. J. Taylor's Ltxlures on Metallurgi/. 



-stroying these combinations, occasionally by presenting other 

 affinities, but in all practical cases assisted by fire. 



The precipitation of copper from solution by iron aiFords 

 an instance, however, of a metal being produced into its me- 

 tallic state from its compound form without the aid of heat. 



The metallic ores, as is well known, are not the produce of 

 all countries, but are limited to situations in which are found 

 certain rocks which inclose them, and which are therefore 

 termed metalliferous rocks. 



These occur only in certain parts of the world, and in these 

 places only can we expect a supply of the metals. England 

 at present holds a distinguished place in the list of mining 

 countries ; our produce of iron, copper, lead and tin, is greater 

 than of any other country, and we also possess considerable 

 quantities of zinc and manganese, widi a proportion of others : 

 such as arsenic, antimony, cobalt and silver, and occasionally 

 small quantities of gold. 



The iron works of Great Britain * arc of immense extent, 

 and are to be found principally in Staffi)rdshire, Shropshire, 

 South Wales, Yorkshire, Derbyshire, North Wales, Dur- 

 ham, and some parts of Scotland. 



Copper is most abundantly produced in Cornwall and De- 

 vonshire f; but certain quantities are also furnished from An- 

 glesea, parts of Ireland, and some from Staffordshire. 



Lead mines are abundant, and very productive on the bor- 

 ders of Northumberland, Cumberland and Durham : next in 

 value may now be placed those of Flintshire and Denbigh- 

 shire. The lead mines of Derbyshire were formerly very im- 

 portant, but are now much dechned in value. Yorkshire has 

 some productive tracts, and this metal is also found in Scot- 

 land, South Wales, Devonshire and Cornwall. 



Tin is a very rare product, and but few parts of the world 

 furnish it; in England it is quite confined to Cornwall and 

 Devonshire, and it has there been worked from the earUest 

 times :f, so as very probably to have been the first article of 

 trade of our island, as we find that the Phoenicians came here 

 to purchase it. 



The ores of zinc are found in Somersetshire, Wales, Corn- 

 wall, and in other places, commonly with the ores of lead. 

 Manganese is pretty abundant in the western parts of Devon- 

 shire and the adjacert parts of Cornwall. 



Tiie quantity of silver raised in this country is certainly not 



* See Mr. Miishet's paper. Phil. Ma^. vol. Ix. p. 401, &c. 



j- See Mr. Taylor's History of Mining. Phil. Mag. vol. v. p. 357. 



X See the Rev. Mr. Gieatheed on the Tin of the Ancients, Phil. Mag. 



TOl.lxi. p. 10ft. yp,.y 



