Manufacturers and Inventors A new Volume of the SCIBIntIFIC AMERICAS commences about the middle of September in eacl year. It is a journal of Scientific, Mechanical, and other improvements; the advocate of industry in alj its various branches. It is published weekly in a form suitable for binding, and constitutes, at the en of each year, a splendid volume of over 400 pages, with a copious index, and from five to six hundred original engravings, together with a great amount ol practical information concerning the progress of invention and discovery throughout the world. The Scientific American is the most widely circulated and popular journal of the kind now published, Its Editors, Contributors, and Correspondents are among the ablest practical scientific men in the world. The Patent Claims are published weekly and are invaluable to Inventors and Patentees, PRIZES—We solicit attention to the splendid Prizes offered for the largest number of subscribers, consisting of a SILVER PITCHER worth $60 ; a set of theCONOGRAPHIO ENCYCLOPEDIA worth $35 ; DEMPSEY'S MACHINERY OF THE NINE-rEENTH CEIfTUI.ahdC. B. Stuart's great work ipon the NAVAL DRY DOCKS OF THE UNITED STATES. Letters should directed (post-paid) to MUNN& CO., 128 Fulton street. New York.