[NM021AAA], Technical Note, Thomas Alva Edison, May 14th, 1887


View document with UniversalViewer   → View document on Archive.org  → Re-use this digital object via a IIIF manifest


[NM021AAA], Technical Note, Thomas Alva Edison, May 14th, 1887

Editor's Notes

719 "The object of this invention is a new process to make wrought iron direct from molten cast iron. The invention consists in running the metal into pigs in the san mould or other receptacle and the ends of which are two iron rods connected to a powerful dynamo electric machine of sufficient ampere capacity to cause the iron to boil & remain liquid for such a time as the carbon is nearly or all burnt out. The current is taken off the rods pulled & the liquid allowed to cool. The ends of the bar are slightly larger than the bar itself to prevent the contact rods from melting. To improve the grain & quality I cause the mould to be placed in a powerful magnetic field so that when it is cooling the particles of iron shall be given a directive force, and thus give a grain & toughness to the iron I am aware that electric currents have been passed through molten iron, and I am also aware that molten iron has been allowed to cool in a magnetic field, but I claim as new the use of a sufficently powerful current to maintain such iron in a molten state for an idefinite time, and also the use of a sufficiently powerful magnetic field as to cause a directive force to be given the particles of iron when nearly set. No effect will be produced with the small magnets hitherto used as iron at the moment of hardening from a molten state has very little magnetic capacity hence the exceedingly powerful magnets of the large modern Dynamo machine will alone produce any effect. Claim, the passing of current to keep in liquid state. Claim powerful field etc Claim both in combination" [2 drawings follow]



Folder/Volume ID


Microfilm ID


Document ID



Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Download CSV | JSON