19. MISCELLANEOUS INFORMATION.-Force of Expansion by Heat; Small Steam-boats, proper dimensions of Engines, Boilers, Propellers. Boats; Incubation, Temperature of; To Make Tracing Paper; Constituents of various substances; Friction, how produced, and Rules for Calculation; Specific Heat Explained; Specific Gravity of Liquids, Solids, Air, and Gases; Gunpowder--Pressure, Heat, and Horse-Power of; Copying Ink, to Make; Heat, its mechanical equivalent explained; Molecules of Matter, size and motion explained; Lightning and Lightning Rods--valuable information; Value of Drainage Explained; Amount of Power at present yielded from Coal by best Engines; Sound--its velocity and action; Liquid Glues, Recipes; Value of Brains; Properties of Charcoal; Height of Waves; Speed of Electric Spark, etc.; Plain Directions, with Engravings, showing how any person can make Electro-Magnets and Electric Batteries at a cost of a few cents; Valuable Recipes.

_The Scientific American Reference Book,_ price only 25 cents, may be had of News Agents in all parts of the country, and of the undersigned. Sent by mail on receipt of the price.

Scientific American, Vol. XXXVII.--No. 2. [New Series.], July 14, 1877 — Part 78

Address MUNN & CO., 37 Park Row, New York,

Scientific American, Vol. XXXVII.--No. 2. [New Series.], July 14, 1877 — Part 78

Will take place at the Auction Rooms of GEO. W. KEELER, 53 Liberty St., N. Y., on July 16, at 12 o'clock. Models now on exhibition. Send for Catalogue.

Scientific American, Vol. XXXVII.--No. 2. [New Series.], July 14, 1877 — Part 78

WOOD & LIGHT MACHINE CO. WORCESTER, Mass. Manufacture of all kinds of IRON-WORKING MANCHINERY, including many novelties. Shafting, Pulleys, &c.

$95 A month and expenses. SALESMAN WANTED to sell to DEALERS. SAMPLES FREE. CANDY & NOVELTIES

LETTERS must have enclosed return postage. H. SMITH & CO., CONFECTIONERS, Cincinnati, O.

POND'S TOOLS ENGINE LATHES, PLANERS, DRILLS, &c.

Send for Catalogue. DAVID W. POND, Successor to LUCIUS W. POND. WORCESTER, MASS.

FIRST PRIZES, CENTENNIAL, PHILA., VIENNA, PARIS, NEW YORK, BALTIMORE, BOSTON.

Send for circular of recent patented improvements,

THE NORWALK IRON WORKS CO., South Norwalk, Conn.

N. F. BURNHAM'S 1874 WATER WHEEL Is declared the "STANDARD TURBINE," by OVER 600 persons who bought and use them with PART and FULL GATE open. Pamphlets Free. N. F. BURNHAM, YORK, PA.

OTIS' SAFETY HOISTING MACHINERY OTIS BROS. & CO., No. 348 Broadway, New York.