MECHANIC;? AND USEFUL ARTS. 67 







rollers to suit the thickness of the "articles to be ground, and also for ad- 

 justing the stones on the central tube or axis. For the purpose of grinding 

 one side only of a steel or metal article at a time, a plain wooden roller 

 is substi tilted for one of the grindstone rollers ; and combined with this 

 arrangement are guide-rollers, for cross-grinding. Scientific American. 



f 



WELDING STEEL ON SHEARS' BLADES. 



The welding of steel upon iron is a very particular operation, and one 

 which requires great experience and care to perform. An improvement 

 in machinery for welding steel on the blades of shears, and finishing them, 

 has been made by Robert Dawson, of Huntington, Connecticut. The 

 principal operating parts are two dies, one being of the form required for 

 the back or outer side of the blade, and the other of the face or inner side 

 of the same, when finished. The former die is arranged in a sliding bed, 

 the latter on a roll above it, the former receiving and forming a solid bear- 

 ing for the whole of the iron part of the blade, and the latter having a flat 

 face to rotate in contact with, and press upon the steel, for welding it to 

 the iron properly, both being caused to move together by gearing between 

 the bed of the lower die, and the roll of the upper die. Scientific American. 



MALLEABLE IRON CASTINGS. 



Mr. H. A. Brooman, of London, lias taken the patent for an invention, 

 which consists of an improved method of preparing wrought iron, so that 

 it may be capable of being poured or cast into moulds, for the production 

 of malleable castings, or articles which shall have all the strength and 

 qualities due to wrought-iron. The invention is designed chiefly for the 

 manufacture of railway wheels ; but it is equally applicable to the produc- 

 tion of other articles. Scrap or wrought-iron may be employed, or bars 

 or plates cut into small pieces, and it must be melted into crucibles, such 

 as are used for melting blister steel. To a charge suitable in amount to 

 the crucible, one-half of one per cent, of charcoal, by weight, one per 

 cent, of manganese and one of sal ammonia are added. The whole is 

 covered from the atmosphere, and melted in a temperature of about 1,500 

 Fahrenheit, which temperature is maintained for three hours. The metal 

 is then poured into moulds. Other carbonaceous matter may be substi- 

 tuted for charcoal. The iron thus cast will, it is stated, be malleable, so 

 as to be capable of being treated under the hammer in the forge, and 

 formed into other shapes, and thus also part of the iron may be shaped in 

 moulds, and part completed by forging, so as to produce intricate shapes 

 and ornamental work. 



NEW MACHINE FOR ROLLING IRON. 



At the British Association, Mr. Clay produced and explained the model 

 of a machine used for rolling taper iron, by which an iron bar may be 



