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 



-Head of frame. B — Frame. C — Cloth. D — Small launder, 



BELOW the frame. F — TUB IN WHICH CLOTH IS WASHED. 



E — Tub set 



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 waj's, 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 perfe'ct 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 conivatio, 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 



