Marine Iron Works. Chicago. Catalogue free. For pnmping engines. J. S. Mundy. Newark, N. J. “U. S.” metal polish. IndTanapolis. Samples free. Presses & Dies. Ferraeute Mach. Co., Bridgeton. N. J. Dynamo castings. TheE. M. Wks.. Ronceverte. W. Va. Handle &Spoke Mchy. Ober Latbe Co.,Chagrin Falls.O. Screw machines, milling: macmnes. and drill presses. The Garvin Mach. Oo.. TAwht and Cana] Sts. New York. Emerson, Smith & Co., Ltd., Beaver Falls, Pa.. wi1l send Sawyer's Hand Book on Circulars and Band Saws free to any address. For the original Bogardus Universal Eccentric Mill, Foot and Power Presses, Drills. Shears, etc., address J.B. & G. F. Simpson, 26to36Rodney St., Brooklyn. N. Y. 'fhe best book for eJectTlClaDS and beginners in electt'lcity is " Kxperimental Science;' by (jeo. M. Hopkins. By mail. f4; Munn & Co.. puhHsherE,361 Broadway. N. Y. WantedA competent draughtsman who has had experience on smaH machine work. Address. stating experience and salary expected, A. R. S.. box 773, New York. losend for new and complete catalogue of Scientific and otber Books for sale by Munn & Co.. 361 Broadway, New York. Free on application.