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 one years experience, and now have imequnled facilities for the peparation of Patent Drawings, Specifications, and the prnsecuUon of Applications for Patent.s in the United States. Canada. and I'-oreign Countries. Messrs. Munn & Co. also attend to the preparation of Caveats, Copyrights for Books, Labels, Reissues, Assignments, and Reports on Infringemems 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, 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 &; CO., SolicUors of Patents, 361 Broadway, New York. BRA NCH OFFICES.-N0. as2 and 624 F Street, Pacific Building, near 7th Street, Washington, D. C.