Use of sails in ancient times, p. 56--Ships with many banks of oars, p. 57--Mediæval ships, p. 59--Modern sailing ships, p. 60--The sailing record of _The Sovereign of the Seas_, p. 60--Early attempts to invent a steamboat, p. 63--Robert Fulton's _Clermont_, p. 64--The steamboat of Blasco de Gary, p. 66--The _Charlotte Dundas_, p. 67--The steamboat invented by Col. John Stevens, p. 68--Fulton designs the _Clermont_, p. 71--The historic trip of the _Clermont_ up the Hudson, p. 71--Sea-going steamships, p. 73--Ships built of iron and steel, p. 74--The _Great Eastern_, p. 76--Principal dimensions of the _Great Eastern_, p. 78--Twin-screw vessels, p. 80--The triumph of the turbine, p. 81--The _Lusitania_ and _Mauretania_, p. 82--Submarine signalling, p. 83--The rescue of the _Republic_, p. 84--How the submarine signalling device works, p. 86--The _Olympic_ and _Titanic_, p. 90--Liquid fuel, p. 90--Advantages and disadvantages of liquid fuel, p. 91. CHAPTER III SUBMARINE VESSELS Slow development of submarine navigation, p. 93--The first submarine, p. 94--Description of David Bushnell's boat, p. 94--Attempts to sink a war vessel during the American Revolution, p. 97--Robert Fulton's experiments, p. 98--The attack on the _Argus_ by Fulton's submarine, p. 100--The attack upon the _Ramilles_ in 1813, p. 102--A successful diving boat, p. 103--The sinking of the _Housatonic_, p. 104--Recent submarines and submersibles, p. 105--The _Holland_, p. 106--The Lake type of boat, p. 108--Problems to be overcome in submarine navigation, p. 109--Present status of submarine boats, p. 111--The problem of seeing without being seen, p. 113--The experimental attacks upon the cruiser _Yankee_ in 1908, p. 115--The possibility of using aeroplanes for detecting the presence of submarines, p. 117. CHAPTER IV THE STEAM LOCOMOTIVE The earliest railroad, p. 119--The substitution of flanged wheels for flanged rails, p. 120--The locomotive of Richard Trevithick, p. 121--The cable road of Chapman, p. 123--Stephenson solves the problem, p. 124--Versatility of Stephenson, p. 125--His early locomotives, p. 126--Stephenson's locomotive of 1825, p. 127--The first passenger coach, p. 128--The Liverpool and Manchester Railway projected, p. 129--Conditions named for testing the competing locomotives, p. 130--The _Rocket_ and other contestants, p. 132--Description of the _Rocket_, p. 133--Improvements on the construction of the _Rocket_, p. 134--Improvements in locomotives in recent years, p. 135--The compound locomotive, p. 137--Advantages of compound locomotives, p. 138--The Westinghouse air brake, p. 141--The "straight air brake," p. 143--The automatic air brake, p. 144--The high-speed air brake, p. 146--Automatic couplings, p. 147--Principle of the Janney coupling, p. 149--A comparison--the old and the new, p. 150. CHAPTER V FROM CART TO AUTOMOBILE