Business and personal 138 Charcoal as fossil 133 Chevreul's black* 137 Cocaine habit, the 128 Correspondence 133 Craze, Yankee, the latest 136 Defense of New York within thirty days' time 132 Dredger, marine, improved* 134 Earthquake, Charleston 133 Electroplating with platinum 132 Emery wheels for gumming saws* 130 Engine, caloric, improved* 127 Eruption in the Tonga group 133 Exhibition, American, London 137 Fish, meat, etc., canned 133 Guns, steel, are they superior? 128 Hats, ladies', protector for* 132 Hydraulic dredging at Washington 134 Injector, Penberthy* 132 Inventions, agricultural 138 Inventions, engineering 138 Inventions, index of 139 Inventions, miscellaneous 138 Life insurance company, a solid 129 Locomotive, three-cylinder 127 Measuring rack, wood, adjustable* 131 Medicine, preventive 129 Nervous patient, treatment, length of 136 Northern lights, the* 135 Notes and queries 138 Patent law, amendment of the, new 128 Patent, steel wire brush 136 Petroleum in Egypt 137 Plasterer's hawk* 131 Pyrofuxin--a new tanning substance from coal 128 Saw gummer, emery vulcanite* 130 Shark, frilled, the* 130 Snails, strength of 137 Sodium, producing, new method of, Castner's 129 Steel rail capacity of the United States 132 Stump puller, improved* 132 Sugar process, new 134 Sun, duration of 134 Thermoscopic balance* 134 Torpedo boat armed with pneumatic dynamite guns* 137 Torpedo, effect of, on an ironclad* 136 Torpedo experiments at Portsmouth* 136 TABLE OF CONTENTS OF SCIENTIFIC AMERICAN SUPPLEMENT No. 582. For the Week Ending February 26, 1887. Price 10 cents. For sale by all newsdealers.