Produced by Lesley Halamek, Juliet Sutherland and the Online Distributed Proofreading Team at http://www.pgdp.net [Illustration] SCIENTIFIC AMERICAN A WEEKLY JOURNAL OF PRACTICAL INFORMATION, ART, SCIENCE, MECHANICS, CHEMISTRY, AND MANUFACTURES. NEW YORK, MARCH 18, 1871. Vol. XXIV.--No. 12. [NEW SERIES.] $3 per Annum [IN ADVANCE.] * * * * * SCIENTIFIC AMERICAN. MUNN & CO., Editors and Proprietors. PUBLISHED WEEKLY AT NO. 37 PARK ROW (PARK BUILDING), NEW YORK. O. D. MUNN. S. H. WALES. A. E. BEACH. VOL. XXIV., NO. 12 ... [NEW SERIES.] _Twenty-sixth Year_ NEW YORK, SATURDAY, MARCH 18, 1871. * * * * * CONTENTS: (Illustrated articles are marked with an asterisk.) *Knots and Splices 175 Influence of Cold on Iron and Steel. 176 Oak Graining in Oil Colors 176 Knots and Splices (Explanation) 177 Hartford Steam Boiler and Insurance Co.'s Report 177 *Improved Spiral Spring for Railway Carriages 178 *Portable Writing and Copying Case 178 How Walking-sticks are Made 178 Flowering of the Victoria Regia 178 Jute 178 Ventilation of the Liverpool Tunnel 178 *Impregnating Wood with Tar, etc. 178 *Boardman's Combined Tool 179 *Belt Tightener 179 Some Things I don't want in the Building Trades 179 *Action of the Reciprocating Parts of Steam Engines 179 *Answer to Practical Problem 179 Reciprocating Parts of Steam Engines 179 Test for White Lead 180 How to Build a Chimney 180 Crystallized Honey 180 Rambles for Relics.--No. 2 180 Silk Culture 181 *Universal Boring Machine 182 *Combined Trunk and Rocking-chair 182 Cosmetics 182 *Smith's Infant Dining-chair 182 The Medicines of the Ancients 182 *Barnes Ventilator for Mattresses 182 Exhibition of the National Photographic Association 182 A Scientific and Technical Awakening 183 The Sherman Process 183 Rubber Tires for Traction Engines 183 Central Shaft of the Hoosac Tunnel 184 A Museum of Art and Natural History 184 Report of Judges, American Institute Fair.