Pulley Blocks,

The celebrated Doyle Blocks have taken premiums over the differential Blocks of all other makers at every Fair where they have been exhibited at the same time. When you buy, see that the Blocks are marked J. J. DOYLE. Pat. Jan. 8, 1861. All others are infringements.

SAMUEL HALL'S SON & CO.,
SOLE MANUFACTURERS.
229 West 10th street, New York.

For Forge and
Mill Work. The M. & T. SAULT CO. Steam Engine Builders & Founders, New Haven, Conn.

EMPLOYMENT.

A MONTH with Stencil Dies.
Samples free. Address

S. M. SPENCER Brattleboro Vt.

THE

Tanite Emery Wheel.

Does not Glaze, Gum, Heat, or Smell. Address

THE TANITE CO.,

Stroudsburg, Monroe Co., Pa.

S. & J. GEAR & CO., Boston, furnish every description of Wood and Iron Working Machinery and Supplies. The best in use, regardless of maker, at lowest possible rates.

Working Models

And Experimental Machinery, Metal, or Wood, made to order, by

J. F. WERNER 62 Center st. N. Y.

cNAB & HARLAN, Manufacturers of Wrought Iron Pipe and Fittings, Brass Cocks, Valves, Gage Cocks, Whistles, Water Gages, and Oil Cups, Harlin's Patent Lubricator, Plumber's Brass Work, Getty's Patent Pipe Cutter, Getty's Patent Proving Pump and Gage. No. 86 John st., New York.

THE

Allen Engine Works,

Fourth avenue and 130th and 131st sts., New York city Manufacturers of

• Porter's Governor,
• The Allen Boiler, and
• Standard Straight Edges, Surface Plates, and
• Angle Plates.

Four first premiums were awarded to us at the Fair of the American Institute, 1870.

Send for our illustrated circular.

L. W. Pond - New Tools.

Extra Heavy And Improved Patterns

ATHES, PLANERS, DRILLS, of all sizes; Vertical Boring Mills, ten feet swing, and under; Milling Machines, Gear and Bolt Cutters; Hand Punches and Shears for Iron.

Office and Warerooms, 98 Liberty st., New York; Works at Worcester, Mass.

A. C. STEBBINS, New York, Agent.

Water-Proof

BUILDING PAPER

(No Tar), for Roofing, Sheathing, Ceilings, Oil-cloths, Shoe Stiffenings, Tags, Trunks, Cartridges, Blasting, Pass-book Covers, Grain and Flour Bins, etc., for sale by

J. HUNTER, Jr.,

Paper Warehouse, 59 Duane st., New York.

Scientific American. For 1871. Twenty-Sixth Year

EVERY NUMBER is printed on fine paper, and elegantly illustrated with original engravings representing

New Inventions, Novelties in Mechanics,
Manufactures, Chemistry, Photography,
Architecture. Agriculture.
Engineering, Science,
and Art.

Farmers, Mechanics, Inventors, Engineers, Chemists Manufacturers and People of all Professions or Trades will find the

Scientific American

of great value and interest.

The Editors are assisted by many of the ablest American and European Writers, and having access to all the leading Scientific and Mechanical Journals of the world, the columns of the Scientific American are constantly enriched with the choicest Information.

An Official List of all the Patents Issued is published Weekly.

The Yearly Numbers of the Scientific American make two splendid Volumes of nearly One Thousand Pages equivalent in size to FOUR THOUSAND ordinary book pages.

SPECIMEN COPIES SENT FREE.

Terms - $3.00 a year, $1.50 half year; Clubs of Ten Copies for one year, at $2.50 each, $25.00,

With a SPLENDID PREMIUM to the person who forms the Club, consisting of a copy of the celebrated Steel Plate Engraving, "Men of Progress."

Address

Munn & Co.,

Publishers of the Scientific American.
37 Park Row, New York.

THE "Scientific American" is printed with CHAS. ENEU JOHNSON & CO.'S INK. Tenth and Lombard sts. Philadelphia, and 59 Gold st. New York.