346 



BOOK VIII. 



plates, because it remains intact, while the rods, when worn by rubbing, can 

 easily be replaced by others. 



Miners use the seventh method of washing when there is no stream of 

 water in the part of the mountain which contains the black tin, or particles of 

 gold, or of other metals. In this case they frequently dig more than fifty 

 ditches on the slope below, or make the same number of pits, six feet long, 

 three feet wide, and three-quarters of a foot deep, not any great distance 

 from each other. At the season when a torrent rises from storms of 

 great violence or long duration, and rushes down the mountain, some of 

 the miners dig the metalliferous material in the woods with broad hoes and 



A — Pits. 



drag it to the torrent. Other miners divert the torrent into the ditches or 

 pits, and others throw the roots of trees, shrubs, and grass out of the ditches 

 or pits with seven-pronged wooden forks. When the torrent has run down, 

 they remove with shovels the uncleansed tin-stone or particles of metal which 

 have settled in the ditches or pits, and cleanse it. 



The eighth method is also employed in the regions which the Lusitanians 

 hold in their power and sway, and is not dissimilar to the last. They drive 



