BOOK VIII. 331 



Many people cover the frame with a green cloth as long and wide as the 

 frame itself, and fasten it with iron nails in such a way that they can easily 



A — Head of frame. B — Frame. C — Cloth. D — Small launder. E — Tub set 



BELOW THE FRAME. F — TUB IN WHICH CLOTH IS WASHED. 



draw them out and remove the cloth. When the cloth appears to be golden 

 because of the particles which adhere to it, it is washed in a special tub and 

 the particles are collected in a bowl. The remainder which has run down into 

 the tub is again washed on the frame. 



fused with vein mining. This passage (xxxiii, 21) is as follows : " Gold is found in 

 ' the world in three ways, to say nothing of that found in India by the ants, and in 

 ' Scythia by the Griffins. The first is as gold dust found in streams, as, for instance, in the 

 ' Tagus in Spain, in the Padus in Italy, in the Hebrus in Thracia, in the Pactolus in Asia, 

 ' and in the Ganges in India ; indeed, there is no gold found more perfect than this, as the 

 ' current polishes it thoroughly by attrition. . . . Others by equal labour and greater 

 ' expense bring rivers from the mountain heights, often a hundred miles, for the purpose of 

 ' washing this debris. The ditches thus made are called corrugi, from our word corrivatio, I 

 ' suppose ; and these entail a thousand fresh labours. The fall must be steep, that the 

 ' water may rush down from very high places, rather than flow gently. The ditches 

 ' across the valleys are joined by aqueducts, and in other places, impassable rocks have to be 

 ' cut away and forced to make room for troughs of hollowed-out logs. Those who cut the 

 ' rocks are suspended by ropes, so that to those who watch them from a distance, the 

 ' workmen seem not so much beasts as birds. Hanging thus, they take the levels and trace 

 ' the lines which the ditch is to take ; and thus, where there is no place for man's footstep, 

 ' streams are dragged by men. The water is vitiated for washing if the current of the 



