AMERICAN INSTITUTE, 647 



|] Journal of the Society of Arts, London.] 



Iron. — This wonderful metal is still apparently not well under- 

 stood, although used from the beginning of the world. 



Some combinations and phenomena, that occur among the ele- 

 ments engaged in the manufacture of iron and the conversion of 

 it into steel. 



Yet everywhere is this the received formula of the composition 

 of steel, namely: That it consists solely of about ninety-nine parts 

 of pure iron, combined with one part of carbon; other elements 

 are accidental and foreign. The steel makers of Sheffield do not 

 believe in the stereotype doctrine of the encyclopedias. Saun- 

 derson, one of the most experienced steel makers, does not believe 

 that " steel is merely iron combined with about one per cent of 

 carbon, or that malleable iron is without any carbon at all, or 

 with less carbon than will form steel. The outer coating of com- 

 mon chilled cast iron is often as hard and untouchable by the file 

 as the best tempered steel." 



An experienced steel worker, a razor, watch spring, needle or 

 surgical instrument maker, takes a piece of unworked rough, 

 black steel, he balances it on his hand, taps it with a hammer, 

 brings out its ring, and its peculiar intonation, is (compared with 

 iron,) to his practised ear, a specific and infallible test of its kind 

 and quality. He next makes it red hot, tries how it draws, that 

 is by repeated blows, elongates the bar, watching as he proceeds 

 the texture of the metal, its adhesiveness, flexibility, indisposition 

 to scale, the character of the marks inflicted by the hammer, &c. 



STEAM PLOWS. 

 Mr. Pell — In the year 1849, Mr. James Usher, of Edinburgh, 

 invented a steam plow, consisting, firstly, in mounting a series of 

 plows in the same plane, around an axis, so that the plows came 

 successively in action; and secondly, in applying power to give 

 rotary motion to a series of plows for tilling the earth, so that 

 the resistance of the earth to the plows, as they entered and 

 travelled through it, caused the machine to be propelled, making 

 it act, when the steam power was applied, in the same way that 

 paddle wheels do in water; the resistance of the earth being 

 greater than the water, the power obtained was proportionally 



