An experience of more than thirty years, and the preparation of not less than one hundred thousand applications for patents at home and abroad, enable us to understand the laws and practice on both continents, and to possess unequaled facilities for procuring patents everywhere. In addition to our facilities for preparing drawings and specifications quickly, the applicant can rest assured that his case will be filed in the Patent Office without delay. Every application, in which the fees have been paid, is sent complete--including the model--to the Patent Office the same day the papers are signed at our office, or received by mail, so there is no delay in filing the case, a complaint we often hear from other sources. Another advantage to the inventor in securing his patent through the Scientific American Patent Agency, it insures a special notice of the invention in the SCIENTIFIC AMERICAN, which publication often opens negotiations for the sale of the patent or manufacture of the article. A synopsis of the patent laws in foreign countries may be found on another page, and persons contemplating the securing of patents abroad are invited to write to this office for prices, which have been reduced in accordance with the times, and our perfected facilities for conducting the business. Address MUNN & CO., office SCIENTIFIC AMERICAN. * * * * * BUSINESS AND PERSONAL. _The Charge for Insertion under this head is One Dollar a line for each insertion; about eight words to a line. Advertisements must be received at publication office as early as Thursday morning to appear in next issue._ Valves and Hydrants, warranted to give perfect satisfaction. Chapman Valve Manuf. Co., Boston, Mass. Brown & Sharpe, Prov., R. I. Best Gear Teeth Cutters and Index Plates at low prices. Send for catalogue. Wanted--Galvanic Battery, Induction Coil, Electro-Magnet. Address, with description and price, Box 1700, Boston, Mass. New Steam Governor.--Entire right for $3,000. For circulars address E. Towns, Cisne, Ill. Gutta Percha, pure and sheeted, for sale in quantities to suit. Anderson & Reynolds, Salem, Mass. The new fragrant Vanity Fair Cigarettes. New combinations of rare Old Perique and Virginia. Wanted--Second-hand Corliss Engine, 100 to 125 H. P. Address P. O. Box 1208, New Haven, Conn. 17 and 20 in. Gibed Rest Screw Lathes. Geo. S. Lincoln, Hartford, Conn. "Downer's Anti-Incrustation Liquid" for Removal and Prevention of Scales in Steam Boilers, is spoken of in highest terms by those who have given it a thorough trial. Circulars and price lists furnished on application. A. H. Downer, 17 Peck Slip, New York.