MESSRS. MUNN & CO., in connection with the publication of the SCIENTIFIC AMERICAN, continue to examine improvements, and to act as Solicitors of Patents for Inventors. In this line of business they have had forty-onv years' experience, and now nave unegualed facilities for the preparation of Pattent Drawings, Specifications, and the prosecution of Application* for Patents in the United States; Canada, and Foreign Countries. .Messrs Munn Co. also attend to the preparation of Caveats, Copyrights for Books, Labels, Reissues. Assignments, and Reports On Infringements of Patents. All business intrusted to them is done with special care and promptness, on very reasonable terms A pamphlet sent free of charge, on application, containing full information about Patents and how to procure them; directions concerning Labels, Copyrights, Designs. Patents, Appeals, Reissues, Infringements, Assignments, Rejected Cases, Hints on the Sale of Patents, etc. We also send ireeof charge, a Synopsis of Foreign Patent Laws, showing the cost and method of securing patents in all the principal countries of the world. MUNN Ac CO., Solicitors of Patents, 361 Broadway, New York. BRANCH OFFICBS.No. 622 and 624 F Street, Pa-ciflc Building, near 7th street, Washington, D. C.