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 A HISTORY OF CORNWALL changes, the stamps becoming six times as effec- tive as they had been before. The lifters were of ash, and their iron heads weighed 140 pounds. 1 Pryce's description also seems to show that all the heads in a coffer operated upon the tin in succession, the blow of the first sending it to the second, and that of the second to the third, after which it was permitted to emerge. 2 We find huddling, 3 sezing, 4 dilleughing, and framing 5 practised as before, but with greater delicacy of manipulation. 6 'Trunking' also had been introduced 7 for the stamped tin stuff which ran from the coffer to the two farther pits. At the semicircular head of the trunk (a pit much like the buddle) a boy stirred these slimes with a small shovel so that the water which ran in might wash both filth and tin over a cross-board about 10 inches deep, from which it passed into the body of the trunk. What remained at the head was framed, and the residue trunked again, and then framed also. The calciners, formerly of moor-stone, were now built of brick, 8 and the burnt leavings, which until 1735 had been thrown away as useless, were after that date reduced to metal. 9 The great work of the nineteenth century has been the provision of more precise and efficient arrangements for dressing, chiefly by the substi- tution of automatic mechanism for human labour, the motive power in almost every case being de- rived from steam. 10 The stamps, for example, are worked almost entirely by steam, and are heavier and more numerous, running in many cases to forty-eight in a set. 11 Among other im- provements have been the crushing mill, the stone breaker, the sizing trommel, the classifier, the continuous jigger, 12 the round buddle, the automatic frame, and the self-acting calciner. The crushing mill was introduced shortly after 1806, by Mr. John Taylor, and from that time to this has formed the chief apparatus for redu- 1 Worth, Historical Notes concerning the Progress of Mining Skill, 39. 2 Pryce, Mineralogia Cornubiensis, ^^. 3 Add MS. 6682, fol. 294-295. 4 Ibid.fol. 295. 6 Ibid. fol. 296. 6 Pryce, Mineralogia Cornubiensis, 133-135. 7 Worth, Historical Notes concerning the Progress of Mining Skill, 39. 8 Pryce, Mineralogia Cornubiensis, 224. 9 Ibid. 230. 10 Worth, Historical Notes concerning the Progress of Mining Skill, 40-41. 11 ' Improvements in Mining,' by Jos. Carne, Trans. Roy. Geol. Soc. Cornto. iii, 61-62. The first steam stamp was at Wheal Vor in 1812 (Hunt, British Mining, p. 725). 12 The first jigging machine erected in Cornwall was introduced by Richard Taylor at the Consolidated Mines, Gwennap, in 1831, and the first continuous jigger was patented in 1843 (Hunt, British Mining, 694-695. See also Proc. of Mining Inst. Cornw. i, No. 3, pp. 34-53)- cing ores for the jigger, buddle, and other con- centrating apparatus. 13 Framing has been so far improved that one hundred frames can now be managed by a girl and a boy. 14 Trunking by machinery was introduced at St. Ives in about the year 1825. The buddle, formerly a shallow oblong trench, is now a circular concave or convex frame revolving slowly beneath a jet of water, centrifrugal force classifying the ores according to their weight. In mining itself more scientific methods of prospecting came into vogue during the eighteenth century. Costeaning and shoding, 1 * although now abandoned, 16 were still practised in the days of Pryce, but already they had been supplemented by boring, 17 and by a better know- ledge of geology. Our ancestors were satisfied to pursue a single vein without suspecting that others might exist near at hand, or if aware of their existence they were apt from want of capital or disinclination to invest it, or perhaps from want of a greater spirit of enterprise to leave them unexplored. At present the lodes are more speedily and fully searched by the practice of driving across the country from north to south, and vice versa, as well as by other methods too technical to be here described. Ventilation, in the eighteenth century, was extended by the provision of boarded channels in the bottoms of adits, by which streams of pure air were carried into the mine. 18 Another method was that of a stream of water passing into one of the shafts, the accompanying air being carried by a pipe placed close to the discharge of the water to the extreme end of the level where required. 19 This process, still used in 1 860, was sometimes assisted by small fans worked by boys. 2 * Other apparatus have been suggested from time to time, 21 but none have proved especially effec- tive, and the ventilation of the tin mines is largely natural, the air finding its way in by certain channels, and out by others. 22 Save where a drift is very long the air is fairly good. Im- proved ventilation brought increased health to the labourer, and added efficiency to his work. 13 Hunt, British Mining, p. 693. 14 Worth, Historical Notes concerning the Progress of Mining Skill, 4041. 15 Ray, A Collection of English Words, 131. 16 ' Improvements in Mining,' by Jos. Carne, Trans. Roy. Geol. Soc. Cornto. iii, 7475. 17 Add. MS. 6682," fol. 281. 18 Pryce, Mineralogia Cornubiensis, 146-147. 19 ' Improvements in Mining,' by Jos. Carne, Trans. Roy. Geol. Soc. Cornw. iii, 64. There does not seem to have been any application of the method of puri- fying the air by fire, such as took place in the coal mines at this time (Galloway, Annals of Coal Mining and the Coal Trade, 326-327, 253-254). 20 Worth, Historical Notes concerning the Progress of Mining Skill, 32. 21 Ibid. 33. Report on Stannary Act Amendment Bill (1887), Q. 366. 552