Page:Federal Reporter, 1st Series, Volume 9.djvu/315

 300 FEDERAL aBPOKTEE. �— one patent being for an improved process in bronzing or coloring iron, and the other being for the iron thus bronzed. The original patent was issued December 15, 1863. �These reissued patents were the subject of litigation before Mr. Justice Clifford in Tucker v. Tucker Manufy Co. 10 0. G. 464; and before Judge Lowell in Tucker v. Burditt, 5 Fed. Eep. 808; and in Tucker y. Dana, 7 Fed. Eep. 213. They have heretofore, to a cer- tain extent, been the subject of discussion in this court. Judge Lowell, in Tucker v. Burditt, describes the patented process, and oonstrues the patent as follows: �" The process consists of cleaning a piece of cast iron of the desired pat- tern from the sand and scale which adhere toit when it cpines frpm the mould, and then coating it with a very thin film of oil, and subjecting it to a high degree qf heat, one or more times, whereby varions colors raay be pro- duced upon the surface of the iron, and reiidered permanent, which, before this invention, were not produced in cast iron, or, if approximated, were not permanent. A film of varnish containing oil may be used Instead of oil, and may infringe the patent ; and so, if the iron is first heated, and then varnished and heated again, the process may be infringed." �With this general definition of the patented process the parties do not now find fault. �The patentee describes the process more at length in the specifica- tion of reissue No. 2,356, and says: �" Metals have heretofore been lacquered or bronzed by the application of a solution of resiu and metallic powders or salts, and dried by exposure to air or heat. Iron has been japanned by covering its surface with oily solutions of asphaltum and pigments, and subsequent application of heat sutHcient to produce hardness. These are well-known operations. My invention consists in a process of covering iron with a very thin coating of oil, and then subject- ing it to heat, the effect of which is to leave upon the iron a firm film, which is very durable, and gives the iron a highly ornamental appearance, like that of bronze. In practice I proceed as follows: The surface of the iron is cleansed from sand, scale, or other foreign matter; and, where fine effeots are desired, the surface is best made smooth or polished. Under given con- ditions of heating and oiling, the finer the polish the lighter is the bronze tint produced. In cases where ornauientation is obtained by relief, the salient parts should be most highly polished or most smoothly surfaced, in order that the colors produced upon Ihem shall not be so deep as it is on those parts which are in the rear, so as to imitate thereby more nearly the effects of genuine bronze, in which the natural oxidation is apt to be worn somewhat away from its salient parts, and therefore lighter in color. When the iron is thus prepared I cover it with a very thin coating of linseed oil, or any oil which is the equivalent therefor, for the purpose here specified, (such a coat- ing as I find best attained by applying the oil with a brush, and then rubbing off the oiled surface thoroughly with a rag, sponge, or other suitable impie- ��� �