i 5 8 



THE POPULAR SCIENCE MONTHLY. 



the " foundry/' while a second man (6) keeps him supplied with 

 metal from another ladle which is skimmed by a boy (7). At 8 is 

 a man cleaning a cast-iron pipe. Pipes made at this period were 

 rarely over three feet in length, and were provided with polygonal 

 flanges at each end for fastening them together with bolts. Pipes 

 two inches in diameter had oval flanges and two bolts ; three- 

 inch pipes had triangular flanges ; eight-inch pipes were square- 

 flanged ; while pipes of twelve and eighteen inches in diameter 

 had flanges of six and eight sides respectively, the number of 

 bolts always equaling the number of angles in the flanges. 



It is not at all certain when the first castings were made from 

 remelted sow, or other form of crude cast iron ; but the crucible 

 has been used for remelting cast iron since a very remote period, 

 and is largely employed in China for that purpose at the present 



Fig. 7. The Process of Casting Crucible-melted Iron. 



day, and the culinary utensils made in that country are remark- 

 able for their thinness. As illustrating the making of castings 

 from crucible-melted iron, we extract Fig. 7, from Reaumur's* 

 work. In this plate "b is a shed, under which is placed a fur- 

 nace c, such as is ordinarily found in the shops of the makers of 

 small castings. This furnace was blown by bellows, held but one 

 crucible, and was quite similar in construction to many furnaces 

 in use at the present day ; d d is a box for holding the molding- 



* L'art de convertir le fer forge en Acier, et L'art d'adoucir le fer fondu. Par Mon- 

 sieur de Reaumur, de l'Academie Royale des Sciences. Paris, 1722. 



