Velocipedes.—Working drawings,scale 3 inches to the foot,with specifications and details enabling any person to construct one. Price 50c. Sent by mail to any address. G. F. Perkins, Haydenville, Mass. Lubricators, oil cups, and gage cocks—" Broughton's " are the best. For circulars address H. Moore, 41 Center st. Wanted—address of makers of lath saws, pump augers, wood lathes, and wood-working machinery generally. G. & A. Lockhart, Bryan, Williams county, Ohio. Wanted—the address of D. F., of Nova Scotia, (see Sci. Am. for Jan. 9,1869, Answers to Correspondents,) and of all others who want a sure scale-preventive. C. P, G., 40 Washington St., Boston, Mass. Who has a machine that will mash and temper clay for bricks Which contains hard lumps and stony substances, neither of which will water soften? A. V. Hurd, Oskaloosa, Iowa. Valuable mill site and country residence for sale. Address J. C. McCarty, Khiuebeck, N. Y, Glynn's anti-incrustator for steam boilers—the only reliable preventive. Causes no foaming, and does not attack the metals of Hie boiler. Liberal terms to Agents. Address II. A. Glynn & Co., 735 Broadway, New, York. Peck's patent drop press. For circulars, address the sole man-ufacturers, Milo Peck & Co,, New Haven, Ct. Woodworking machinery.—Persons having machinery suitable for planing mill and sash factory, Can hear of a purchaser by addressing G. B. Wilson, Clarksville, Tenn. W. J. T.—We think the patent asbestos roofing manufactured by H. W. Johns, of this city, is the best substitute for tin or slate. It is cheap and easily applied. Inventors and patentees wishing to get small, light articles manufactured for them in German silver or brass, address SehoSeld Brothers, Plainville, Mass, Tempered steel spiral springs. John Chatillon, 91 and 93 Cliff st., New York. Two saw mills for sale. C. Bridgman, St. Cloud, Minn. Eockwood, 839 Broadway, N". Y, photographs architectural or mechanical drawings and plans to a scale. Also.photographs of machinery. For solid wrought-iron beams, etc., see advertisement. Address Union Iron Mills, Pittsburgh, Pa., for lithograph, etd. Scientific Purchasing Agency.—Scientific, Mechanical, Mining, and Agricultural Books, Instruments,etc, for sale at publishers' or manufacturers' prices. Address Saltiel & Co., Postofflce Box 448, New York city, or 37 Park Row. Change Gear-wheel Tables.—See Walter& Son's advertisement. Punching and shearing machines. Doty Manufacturing Co., Janesville, Wis. Specialties in the Machinists' line. Parties desiring work of a special character address S. W. Gardiner, 6 Ailing st., Newark, ST. J. " The greatest attraction in the Mechanics' Hall, at the New York State Fair.was the wonderful scroll saw exhibited by J. W. Mount." —Sec New York Times, Oct. 16,1868. All who are interested in scroll saws should address the exhibitor at Medina Iron Works Medina, N. Y. Ericsson's Caloric Engines.—Where a light, safe, economical power is required, these engines—of late greatly improved in construction as well as reduced in price—answer an admirable purpose. Apply to James A. Robinson, 164Duane st., New York. Ask for Olmsted's oiler,—the best made. Sold everywhere. The manufacture and introduction of sheet and cast metal small wares is made a specialty by J. H. White, of Newark, N. J. For descriptive circular of the best grate bar in use, address Hutchinson & Laurence, No. 8 Dey st., New York. An experienced engineer, who for years has been engaged as superintendent and mechanical draftsman n a machine shop.wishes a sim. ilar position in some establishment. Good references given. Address Engineer, Postofflce Box 8443, Boston, Mass. American Needle Company, general needle manufacturers, and dealers in sewing-machine materials. Hackle, gill, comb, card pins, etc., to order J. W. Bartlett, Depot 569 Broadway, New York. " Broughton's " oilers are the most durable and effective. Responsible and practical engineers pronounce the Tupper Grate Bar the best in use. Send for a pamphlet. L. B. Tupper, 120 West st., N.T. Iron.—W. D. McGowan,iron broker,73 Water St., Pittsburgh,Pa. N. C. Stiles' pat. punching and drop presses, Middletown, Ct. Winans' boiler powder, N. Y., removes and prevents incrustations without injury or foaming ; 12 years in Use, Beware of imitations. The paper that meets the eye of all the leading manufacturers throughout the United States-The Boston Bulletin. $4 a year.