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BOOK V.

into a dish placed underneath to prevent any of the metal from falling tothe ground. They break a hard vein loose from the footwall by blows witha hammer upon the first kind of iron tool 13 , all of which are designated byappropriate names, and with the same tools they hew away the hard hanging-wall rock. They hew out the hangingwall rock in advance more frequently, therock of the footwall more rarely; and indeed, when the rock of the footwallresists iron tools, the rock of the hangingwall certainly cannot be broken unlessit is allowable to shatter it by fire. With regard to the harder veins which aretractable to iron tools, and likewise with regard to the harder and hardestkind of hangingwall rock, they generally attack them with more powerfuliron tools, in fact, with the fourth kind of iron tool, which are called by theirappropriate names ; but if these are not ready to hand, they use two orthree iron tools of the first kind together. As for the hardest kind of metal-bearing vein, which in a measure resists iron tools, if the owners of theneighbouring mines give them permission, they break it with fires. But ifthese owners refuse them permission, then first of all they hew out the rock ofthe hangingwall, or of the footwall if it be less hard ; then they place timbersset in hitches in the hanging or footwall, a little above the vein, and fromthe front and upper part, where the vein is seen to be seamed with smallcracks, they drive into one of the little cracks one of the iron tools whichI have mentioned ; then in each fracture they place four thin ironblocks, and in order to hold them more firmly, if necessary, they placeas many thin iron plates back to back; next they place thinner ironplates between each two iron blocks, and strike and drive them byturns with hammers, whereby the vein rings with a shrill sound; and themoment when it begins to be detached from the hangingwall or footwallrock, a tearing sound is heard. As soon as this grows distinct the minershastily flee away ; then a great crash is heard as the vein is broken and torn,and falls down. By this method they throw down a portion of a vein weigh-ing a hundred pounds more or less. But if the miners by any other methodhew the hardest kind of vein which is rich in metal, there remain certaincone-shaped portions which can be cut out afterward only with difficulty. Asfor this knob of hard ore, if it is devoid of metal, or if they are not allowed toapply fire to it, they proceed round it by digging to the right or left, becauseit cannot be broken into by iron wedges without great expense. Meantime,while the workmen are carrying out the task they have undertaken, thedepths of the earth often resound with sweet singing, whereby they lighten atoil which is of the severest kind and full of the greatest dangers.

As I have just said, fire shatters the hardest rocks, but the method of itsapplication is not simple 14 . For if a vein held in the rocks cannot be hewn

13 The various kinds of iron tools are described in great detail in Book VI.

14 Fire-setting as an aid to breaking rock is of very ancient origin, and moreover itpersisted in certain German and Norwegian mines down to the end of the 19th century—270 years after the first application of explosives to mining. The first specific reference tofire-setting in mining is by Agatharchides (2nd century b.c.) whose works are not extant,but who is quoted by both Diodorus Siculus and Photius, for which statement see note 8, p.279. Pliny (xxxm, 21) says : “ Occasionally a kind of silex is met with, which must be“ broken with fire and vinegar, or as the tunnels are filled with suffocating fumes and smoke,