M ESSKS. MUNN & CO., in connection with the publication of the SCIENTIFIC AMERICAN, continue to examine improvements, and to act as Solicitors of Patents for In ventors. In this line of business they have had forty-one yean' experience, and now have unequaied facilities for the preparation of Patent Drawings, Specifications, and the prosecution of Applications for Patents in the United States, Canada, and Foreign Countries. Messrs. .M unn & Co. also attend to the preparation of Caveats, Copyrights for Books, Labels. Reissues, Assignments, and Reports on Infringements nl 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, free of charge, a Synopsis of Foreign Patent Laws, showing the cost and method of securing patents in all the principal countries of the world. MUNN fc CO., Solicitors of Patent*, 361 Broadway, New York. BRANCH OFFICER—No. 622 and 684 F Street, Pa-clflc Building, near 7th Street, Washington. D. C.