MECHANICS AND USEFUL ARTS. 45 



of the press was suspended when the part welded was brought down to 

 the thickness of the bars. After cooling, the welded part was cut 

 through to examine the inside, which was found perfectly compact. 

 To try it, one of the halves was placed under a forge-hammer weigh- 

 ing l,800kil., and it was not until the third stroke that the welding 

 was discovered." 



Alluding to the above, the London Artisan says : 



A highly ingenious form of hydraulic press for forging metals was 

 also patented some time since by Mr. Bessemer. Its construction 

 was as follows : 



An ordinary ram of a hydraulic press is in communication through a 

 pipe with the usual force-pump plunger, driven with a crank on a shaft 

 provided with a heavy fly-wheel. The barrel, in which is working the 

 plunger, is unprovided with valves, and is continued as a simple pipe 

 till it communicates with the cylinder of the press. The water between 

 the plunger of this kind of pipe and the ram thus acts as a communica- 

 tor of motion between the two, and they rise and fall through distances 

 varying respectively as the areas of the plungers. It will be seen that 

 the heavy fly-wheel does the principal work in compressing ; for as 

 soon as the rams the propelling plunger and the driven plunger 

 meet with resistance, the inertia of the heavy fly-wheel at once comes into 

 play. We do not know whether this invention has been found suc- 

 cessful in practice ; and a yet more recent patent of Mf. Bessemer em- 

 bodies the plan of supporting the bearings of the bottom roll of mills 

 for rolling armor plates on a hydraulic ram. This ram is in communi- 

 cation with water pressure, which can be let on or off, as required, by 

 means of a valve. In case the armor plate being rolled should stick 

 as often takes place the water below the ram is let out, with the result 

 of relieving the plate from pressure. 



It is scarcely possible to over-estimate the importance of the appli- 

 cation of the hydraulic press for forging purposes, and it may be 

 ranked almost as high in the scale of practical improvements in working 

 iron as the introduction of the rolling mill, and at least as high as the 

 introduction of the steam hammer. It would seem to fit in with the 

 recent inventions, giving us a command over the production of steel in 

 large masses, affording, as it does, means of working a substance of 

 much more delicate manipulation than even wrought iron. Nor does 

 the use of the hydraulic press seem to be confined to working of iron 

 and steel in an incandescent state, as is evidenced in the remarkable 

 production of steel tubes drawn cold by hydraulic pressure. 



NEW PLAN FOR THE PRODUCTION OF CAST STEEL FROM PIG 



IRON. 



M. Cazanave, a French inventor, has recently devised the following 

 new plan for producing cast steel directly from pig iron. 



The foundation of this new method is the influence of steam on a thin 

 stream of pig iron. If we take an iron tube of a certain diameter with 

 sides of the necessary strength, form a ring out of it, and fix on its cir- 

 cumference towards the centre three or more tubes, we have a tube 

 ring with three or more radii. The radius is made fast to the tubular 

 pipe ; the ends of these tubes, which are open, do not quite reach to 

 the centre of the ring, and have, therefore, between the ends an empty 



