one foot per see(rod to one foot per minute, whereas annealing operations require several hours or days for their comt)letion. This process will be found to be peculiarly adapted to the production of steel shat'ting, piston rods, and also f()l" very light work, such as burnished steel tbr pivots tbr watches and c'locks, (etc., in which latter ease it is evident that the mechanism employed must be of a reduced size suitable for the work to t)e accoml)lished.
Comparing the mechanical effect of this process with other wellknown processes, the difference is very marked. Wrought iron possessing a tensile strength of 50,000 t)ouuds per square inch, and mt elastic limit of 30,000 pounds per square inch, and exhibiting an elongation of 25 per cent., will, when eold-rolled by the Lauth proeess, possess a tensile strength of 68,600 pounds, and an elastic limit of 59,600 pounds, but the ductility is redueed to an eh)ngation of' 6 per cent. When such cold-rolled iron is annealed it is found to possess a tensile strength of 48,700 t)ounds, an elastic limit of 32,000, and an elongation of 15 per cent.
Professor R. H. Thurston, in his paper on " Mechanical Treatment of Metals,"* said : " All known and actually practiced methods of so altering the character of the metals used by the engineer, involve, directly or indirectly, the elevation of the original elastic limit of the material." In this l)roeess, however, the elastic limit is slightly reduced.
In eonelusion i would add, that the phenomena exhibited in this l)roeess invite further research into the laws of mole('ular l)hysi(;s.