BOOK II. 41 



sleep to watchmen and awoke slumberers^*. Therefore it seems that the 

 divining rod passed to the mines from its impure origin with the magicians. 

 Then when good men shrank with horror from the incantations and rejected 

 them, the twig was retained by the unsophisticated common miners, and 

 in searching for new veins some traces of these ancient usages remain. 



But since truly the twigs of the miners do move, albeit they do not 

 generally use incantations, some say this movement is caused by the 

 power of the veins, others say that it depends on the manipulation, and 

 still others think that the movement is due to both these causes. But, in 

 truth, all those objects which are endowed with the power of attraction 

 do not twist things in circles, but attract them directly to themselves ; for 

 instance, the magnet does not turn the iron, but draws it directly to itself, 

 and amber rubbed until it is warm does not bend straws about, but simply 

 draws them to itself. If the power of the veins were of a similar nature to 

 that of the magnet and the amber, the twig would not so much twist as 

 move once only, in a semi-circle, and be drawn directly to the vein, and unless 

 the strength of the man who holds the twig were to resist and oppose the 

 force of the vein, the twig would be brought to the ground ; wherefore, 

 since this is not the case, it must necessarily follow that the manipulation 

 is the cause of the twig's twisting motion. It is a conspicuous fact that 

 these cunning manipulators do not use a straight twig, but a forked one 

 cut from a hazel bush, or from some other wood equally flexible, so that if it 

 be held in the hands, as they are accustomed to hold it, it turns in a circle 

 for any man wherever he stands. Nor is it strange that the twig does not 

 turn when held by the inexperienced, because they either grasp the forks of 

 the twig too tightly or hold them too loosely. Nevertheless, these things 

 give rise to the faith among common miners that veins are discovered by 

 the use of twigs, because whilst using these they do accidentally discover 

 some ; but it more often happens that they lose their labour, and although 

 they might discover a vein, they become none the less exhausted in 

 digging useless trenches than do the miners who prospect in an unfortunate 

 locality. Therefore a miner, since we think he ought to be a good and 

 serious man, should not make use of an enchanted twig, because if he is 

 pnident and skilled in the natural signs, he understands that a forked stick 

 is of no use to him, for as I have said before, there are the natural indica- 

 tions of the veins which he can see for himself without the help of twigs. 

 So if Nature or chance should indicate a locality suitable for mining, the 

 miner should dig his trenches there : if no vein appears he must dig 

 numerous trenches until he discovers an outcrop of a vein. 



A vena dilatata is rarely discovered by men's labour, but usually some 

 forc'e or other reveals it, or sometimes it is discovered by a shaft or a tunnel 

 on a vena profunda^^. 



^^Odyssey xxiv., i, etc. The Caducens of Hermes had also the power of turning 

 things to gold, and it is interesting to note that in its oldest form, as the insignia of heralds 

 and of ambassadors, it had two prongs. 



*^In a general way venae prof undue were fissure veins and venae dilatatae were sheeted 

 deposits. For description see Book III. 



