This is believed to be the oldest Foundry in Louisville, and one of the largest and most extensive in the Western country. Their engines have a wide-spread reputation in the West and South, and are well known and highly prized by Southern boat builders. Their fidelity in materials and workmanship, their promptness in the execution of orders, and their extensive assortment of the latest and most improved style of tools and patterns, combined with the well-known enterprise of the gentlemen who compose the firm, have all contributed to build up for this establishment a business and a reputation which reflects credit upon this branch of manufacture in the city. Steam engines are built by them in complete running order and ready for use, the purchaser not being required to go to any other factory for any of his order. Their business relations extend over a very large surface of country, and bring to the city much foreign trade. Besides their engines for boats, they also manufacture machinery of all kinds, Car wheels, Axles and Car castings of all descriptions, together with Iron and Brass castings and Wrought Iron work. This foundry employs one hundred and twenty hands, and uses six hundred tons of pig iron annually, besides other materials in proportion. UNION FOUNDRY. ROACH & LONG, MANUFACTURERS OF STEAM MACHINERY OF EVERY DESCRIPTION, SUGAR MILLS, COTTON GINS, &C., &C. Main street, near Ninth. This concern, although not so old as many of its class is yet one deserving especial notice. The description of the business of this foundry differs very little, if at all, from some of those already noticed. The quality of work is in the highest degree creditable to the proprietors and profitable to this department of manufactures in the city. Both members of the firm are thorough practical workmen, having been regularly brought up to the business, and hence the work which proceeds from this foundry compares favorably, not only with any in the city, but with similar kinds of manufactures in any part of the country. Like most of our large machine foundries, the Union has extensive connection with the Southern markets.--They have frequently forwarded as many as seven cotton-gins within a fortnight, to different ports on the Mississippi river. Their Sugar Mills, wherever they have been used, are eminently successful in their operation. The casting of Chairs and Frogs for Railroads has also been extensively carried on at this foundry. In the great department of their business, the manufacture of Steam Engines for Boats, the Union Foundry enjoys a reputation which cannot be anywhere surpassed. They have built all sizes of engines, and are at present engaged upon a pair of engines with thirty inch cylinder and ten foot stroke. Indeed the heaviest castings of all sorts are constructed as readily and perfectly as the lightest, and are made to work with equal ease and precision.