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AXXALS XEW YORE ACADEMY OF SCIENCES 



Following copper, we may take up lead and zinc,, which are the next 

 metals in amount of production. Of the three, zinc is the least in total 

 tons and in total value. We may gain some idea of the relations from 

 the small table given below, in which zinc is taken as unity and the fig- . 

 ures relate to 1908. Price per 



Amount Value Pound 



Zinc 1.0 1.0 1.0 



Lead 1.6 1.45 0.9 



Copper 2.46 7.0 2.8 



Thus we see that the lead production is one and three fifths that of 

 zinc, and the copper is two and one half times ; that the lead is about one 

 and one half times the value of the zinc, and the copper is seven times ; 

 and that zinc is worth more per pound than lead and only about one third 

 as much as copper. The red metal is not only produced in greater 

 amount, but is worth more per pound and in the aggregate than both the 

 others taken together. 



Among the nations of the world, the United States has become the 

 chief contributor of lead and yields year by year proportions varying from 

 37 to 33 per cent, of the total. The next country is Spain with about 

 two thirds as much, and Germany follows with three fifths. 



In this country, the state of Missouri is the heaviest contributor and is 

 responsible for practically 40 per cent, of the total. Idaho is next with 

 about 32 per cent, and Utah follows Math 13 to 14. The western lead 

 all carries silver. The precious metal is an important factor in the value 

 of the product. AMien we come to forecast the future, it is not possible 

 to see more than a few years in advance or to speak in more than a general 

 way. The miners would be glad to be assured of reserves of ore for a 

 goodly period of years, but it is seldom possible or practicable to demon- 

 strate their presence. Operations necessarily continue with a few years' 

 supply blocked out in advance of the actual mining, and the hope is main- 

 tained that more ^-ill be found. Very often the expectations prove Justi- 

 fied. We may, therefore, in a measure forecast future experience some- 

 what by the past. In the Missouri lead region, mines have been operated 

 for forty or fifty years, not on so large a scale at the outset as now, but 

 continuously. For some years at least, no change may be anticipated. 

 In Idaho, the lead ores are now known to continue to depths of nearlv 

 2,000 feet beneath the overlying surface and to be holding out without 

 essential change in character. In Missouri, however, the mines never 

 have been very deep, that is over three or four hundred feet, and the 

 compensation comes in wide horizontal extent. 



Some of the old time heavy producers have greatly declined. N'evada, 



