343. Possible Aspect of the Forests of the Coal Age 754 344. The Fireside 756 345. View on Hyde and Egbert’s Farm, Oil Creek 761 346. View of City of London Gas-Works 764 347. Section of Gas-making Apparatus 765 348. The Retort 767 348_a_. Retort House of the Imperial Gas-Works 768 349. The Gas Governor 770 350. Bunsen’s Burner 772 351. Faraday’s Ventilating Gas-Burner 773 351_a_. Diagram 778 351_b_. Diagram 778 351_c_. Diagram 779 351_d_. Diagram 779 351_e_. Diagram 780 352. Apparatus for making Magenta 781 353. Iron Pots for making Nitro-Benzol 784 354. Section of Apparatus for making Nitro-Benzol 785 355. Apparatus for making Aniline 786 356. Section of Hollow Spindle 787 357. Portrait of J. Prescott Joule, F.R.S. 801 LIST OF PLATES. PLATE I. TO FACE THE GREAT WHEEL IN ACTION _Title page_ PLATE II. NORTH-EASTERN RAILWAY LOCOMOTIVE 18 PLATE III. THE GREAT STEAM HAMMER, ROYAL GUN FACTORY, WOOLWICH 28 PLATE IV. THE AMERICAN TRACT SOCIETY BUILDING 76 PLATE V. GENERAL VIEW OF THE GREAT WHEEL AT EARL’S COURT 84 PLATE VI. MOUNT WASHINGTON INCLINED TRACK 124 PLATE VII. PIKE’S PEAK RAILROAD, ROCKY MOUNTAINS 128 PLATE VIII. THE “CLERMONT” FROM A CONTEMPORARY DRAWING 130 PLATE IX. THE “MARY POWELL” 144 PLATE X. THE “NEW YORK” 148 PLATE XI. H.M.S. “THE TERRIBLE” 168