342 On the Cutting of Steel by Soft Iron^ 



ing a mixture of salts, having these acids in their composi- 

 tion, that the whole may pass to the state of nitrites by the' 

 agency of air, heat, and moisture. 



Variable quantities of these two acids may be formed, 

 under the different circumstances in which the two gases 

 are mixed ; " this perfectly explains the differences in the 

 results of those who have operated with them." 



A great degree of reliance may be placed on the indica- 

 tions of nitrous gas as employed in the method of Gay Lus- 

 sac ; but for accurate experiments it will probably never 

 supersede the use of hydrogene and the electric spark in 

 Volta's eudiometer, or in the improved form of that appa- 

 ratus proposed by Dr. Ure. 



November 12, 1823. 



Art. XVHL— O/i the Cutting of Steel by Soft Iron. 

 Editor. 



At page 336 Vol. 6 of this Journal, the remarkable fact 

 that soft iron, in rapid revolution, will cut the hardest steel, 

 is described by the Rev''d. Herman Daggett. This fact 

 does not appear, as far as I am informed in books, nor 

 have I found that it was before known to practical men ; it 

 seems to have been discovered by the Shakers, who are 

 remarkable for the neatness and expertness of their me- 

 chanical operations. As it is desirable that the experience 

 of others, on this subject, should be made known, I will 

 now add, that in June last. I saw Professor Robert Hare at 

 Philadelphia, execute, with a common foot lathe, opera- 

 lions similar to those described by Mr. Daggett; they were 

 however less energetic and decisive, as the machine did not 

 produce so rapid a motion as that of Mr. Barnes. 



I have however since repeatedly seen the experiraenf 

 succeed, in the most perfect manner, at the manufactory of 

 •arms, belonging to Eli Whitney Esq. near this town. As 

 water power is here applied with great facility find energy, a 

 wheel of soft and very thin plate iron, six inches in diame- 

 ter, and furnished with an axis, was made to revolve, with 

 such rapidity, that the motion became entirely impercepti- 

 ble, and the wheel appeared as if at rest. When pieces- ot 

 .the best and hardest steel, such as files, and the steel of 



