BOOK XXXIV. xLi. 143-146 



closely allied to lead, others a brittle and coppery 

 kind that is specially to be avoided for the require- 

 ments of wheels and for nails, for which purpose the 

 former quaUty is suitable ; another variety of iron 

 finds favour in short lengths only and in nails for 

 soldiers' boots ; another variety experiences rust 

 more quickly. All of these are called ' stricturae.' 

 edging ores,' a term not used in the case of other 

 metals ; it is, as assigned to these ores, derived from 

 striiigere aciem, ' to draw out a sharp edge.' There is 

 also a great difference between smelting works, and 

 a certain knurr of iron is smelted in them to give 

 hardness to a blade, and by another process to giving 

 sohdity to anvils or the heads of hammers. But the 

 chief difference depends on the water in which at 

 intervals the red hot metal is plunged ; the water 

 in some districts is more serviceable than in others, 

 and has made places famous for the celebrity of their 

 iron, for instance Bambola and Tarragona in Spain 

 and Como in Italy, although there are no iron mines 

 in those places. But of all varieties of iron the 

 palm goes to the Seric, sent us by the Seres'^ with 

 their fabrics and skins. The second prize goes to 

 Parthian iron ; and indeed no other kinds of iron 

 are forged from pure metal, as all the rest have a 

 softer alloy welded with them. In our part of the 

 world, in some places the lode supplies this good 

 quality, as for instance in the country of the Norici, 

 in other places it is due to the method of working, 

 as at Sulmoiia, and in others, as we have said, it is due § 144. 

 to the water ; inasmuch as for giving an edge there 

 is a great difference between oil whetstones and 

 water whetstones, and a finer edge is produced by 

 oil. It ^ is the custom to quench smaller iron forgings 



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