MECHANICS AND USEFUL ARTS. 79 



away with the necessity of rivets for the purpose of fastening iron- 

 work together, where it is used for grating of any description. The 

 manufacturers are enabled to weave iron as large as railroad bars, or 

 the smallest description of wire. Journal of Commerce. 



SHEET-IRON PIPES. 



SHEET-IRON pipes of a new manufacture have lately been intro- 

 duced into England, from France, where they have been in use for 

 several years. They are made of sheet-iron, which is bent to the re- 

 quired form and then strongly riveted together, after which they are 

 coated with an alloy of tin, and the longitudinal joints are soldered so 

 as to render them both air-tight and water-proof. In order to give 

 them more stiffness, they are next coated on the outside with asphalte 

 cement, and, if they are intended to be used as water-pipes, the in- 

 side is also coated with bitumen, which resists like glass, the ac- 

 tion of acids and alkalies. They are so elastic that they will bear a 

 considerable deflection without injuring the pipes, or causing any 

 leakage at the joints. The vertical joints screw together in the same 

 manner as cast-iron gas-pipes. These pipes have been used for wa- 

 ter, for gas, and for draining, and are found to be more economical 

 than cast-iron, besides being less liable to leak, and for water-pipes 

 they are more healthy than the common ones. 



CAST IRON PIPES. 



MR. THOMAS J. LOVEGROVE, of Baltimore, has made an important 

 invention in the manufacture of iron pipes, whereby much time and 

 expense are saved. It is an ingenious application of the known 

 effect of centrifugal force, and it will do away with the old and labori- 

 ous plan of making moulds for each pipe. Any sort of pipes can be 

 made in this way. 



By the ordinary mode of casting pipe, it is necessary to make a 

 sand-mould for every separate piece of pipe, and a " core," which is 

 formed by wrapping hay around a rod, this again being coated care- 

 i Lilly with clay to preserve the tubular or hollow form of the pipe. 

 The time thus occupied may be easily imagined, and the consequent 

 gain that must necessarily attend any plan by which all this is dis- 

 pensed with. 



The invention of Mr. Lovegrove consists of an iron mould, sus- 

 pended horizontally, and arranged for the introduction of the melted 

 metal by means of a trough at one end. As the metal is introduced, 

 a slight depression at one end is effected by means of suitable tackle, 

 and the revolution of the mould immediately commences ; by the time 

 all the metal is introduced, the mould is elevated to its true position, 

 the gravitation having carried the fused metal to the end of the 

 mould, and it suddenly revolves for about half a minute with con- 

 siderable velocity, distributing the metal equally to the surface, 

 throughout the entire length of the mould, from the centrifugal force 

 of the revolution. The vacancy in the centre is of course regulated 



