40 ECONOMICAL MINERALOGY. 



ing the ore to the state of rough bar, one hundred and fifty pounds being the usual weight of 

 the loup. Now analysis shows that the Arnold ore contains from sixty-eight to seventy-one 

 per cent of metaUic iron ; and although great allowance is to be made for the waste necessarily 

 attendant upon metallurgic processes, we may fairly conclude that when it amounts, as it 

 does in the present case, to a hundred per cent, there must be some defect in the process of 

 reduction. 



The clay iron-stone so extensively used in GreSt Britain, seldom contains more than thirty- 

 five per cent of metallic iron ; and yet it is stated that three tons of this ore yield about one 

 ton of cast iron, and this last again loses about ten or twelve per cent of its weight by con- 

 version into refined iron, so that about three and a half tons of the ore yield a ton of refined 

 iron. The difference will be more apparent from the following statement. 



Three tons of Arnold ore, at 70 per cent, = 4,704 lbs. metallic iron. 



Three and a half tons clay iron-stone, at 35 per cent, . = 2,744 " do. do. 



Diiference, 1,960 lbs. 



Showing that, by the process of which we are now speaking, for every ton of rough bar iron 

 obtained, there is a waste of nearly another ton of metallic iron. And in this estimate, nothing 

 has been allowed for the loss which these bars suffer in the various operations to which they 

 are subjected previously to their preparation for the manufacture of nails, &c. 



The important influence which the facts just stated must exert upon the manufacture of 

 iron in the district where this process is almost exclusively employed, can scarcely be doubted, 

 when it is stated that the price of ore is sometimes not less than five dollars the ton. To all 

 this should be added the waste of fuel, which I am satisfied may be fairly set down to this 

 mode of manufacture. 



Another, and perhaps more serious objection to the process under examination, is the want 

 of uniformity in the texture of the iron, and its unfitness for many uses to which this metal is 

 applied. This is owing to the alternate mixture of steely grains with those of the malleable 

 iron, a result which no care can prevent. Hence chain cables manufactured from this kind 

 of iron, although they are sufficiently tough in some parts, in others have a tenacity so in- 

 considerable as to be easily destroyed by the weight applied to them. To the same want of 

 uniformity in the texture, is to be ascribed the rapidity with which they are oxidated by ex- 

 posure to the atmosphere. 



In adverting to these facts, I trust that 1 shall not be accused of a want of interest in our 

 manufactures. They are, it is believed, well known to most of our iron masters ; and my 

 object in thus noticing them, is to urge the importance of the introduction of a less exception- 

 able process than that which has just been described. The iron ores in various parts of the 

 State will not suffer in the comparison with any in the world ; and there is no reason, if proper 

 attention be paid to the manufacture, why the iron obtained from them should not be as valuable 

 as any other. 



The Dannemora iron ore, from which the most celebrated Swedish iron is obtained, is similar 



