WM. H. APPLETON, WILLIAM H. BEERS, WILLIAM A. BOOTH, HON. BENJ. H. BRISTOW, HENRY BOWERS, JOHN CLAFLIN, ROBERT B. COLLINS, R. SUYDAM GRANT, ELIAS S. HIGGINS, WALTER H. LEWIS, EDWARD MARTIN, RICHARD MÜSER, GEORGE H. POTTS, C. C. BALDWIN, JOHN N. STEARNS, WM. L. STRONG, ALEX. STUDWELL, HENRY TUCK, A. H. WELCH, L. L. WHITE. THEODORE M. BANTA, Cashier. D. O'DELL, Superintendent of Agencies. A. HUNTINGTON, M.D., Medical Director. WILLIAM H. BEERS, President. HENRY TUCK, Vice-President. ARCHIBALD H. WELCH, 2d Vice-President. RUFUS W. WEEKS, Actuary. Advertisements. =Inside Page, each insertion 75 cents a line.= =Back Page, each insertion $1.00 a line.= The above are charges per agate line--about eight words per line. This notice shows the width of the line, and is set in agate type. Engravings may head advertisements at the same rate per agate line, by measurement, as the letter press. Advertisements must be received at publication office as early as Thursday morning to appear in next issue. SPECIAL MACHINERY =For Grinding and Polishing= =Manufactured by The Somersworth Machine Co.,= =E. R. WARE, Agt.,= =154 Lake Street, CHICAGO.= Write for Circulars. CALDWELLS CONVEYOR CALDWELL'S SPIRAL STEEL CONVEYOR, 131-133 West Washington St., Chicago, Ill ICE-BOATS--THEIR CONSTRUCTION and management. With working drawings, details, and directions in full. Four engravings, showing mode of construction. Views of the two fastest ice-sailing boats used on the Hudson river in winter. By H. A. Horsfall, M.E. Contained in SCIENTIFIC AMERICAN SUPPLEMENT, 1. The same number also contains the rules and regulations for the formation of ice-boat clubs, the sailing and management of ice-boats. Price 10 cents. CATALOGUES FREE TO ANY ADDRESS TOOLS OF ALL KINDS TOOLS GOODNOW & WIGHTMAN BOSTON [Illustration] Smith Machine for making Thimbles or Sockets for Steam Boilers. Can make over 800 per day, all uniform in diameter and perfectly parallel, leaving no space for the bolts to bend in the thimble, making it almost impossible to make a tight boiler, for when the hydrostatic pressure is applied, straighten the bolt enough to make it leak; often has to be taken out. Address JAMES T SMITH, People's Machine & Boiler W'ks, Baltimore, Md. VENTILATION.--Great importance of ventilation. The vitiation of air that is constantly going on in inhabited places, exhaustion of oxygen by gas, candles and lamps. Ventilation by natural and artificial means. Contained in SCIENTIFIC AMERICAN SUPPLEMENT, No. =525.= Price 10 cents. To be had at this office and from all newsdealers. =A BIG OFFER.= To introduce them, we will =Give Away,= 1,000 Self-Operating Washing Machines. If you want one send us your name, P. O. and express office at once. =The National Co., 23 Dey St., N. Y.=