LIGHT 380 SOME PHENOMENA OF LIGHT 382 VELOCITY OF LIGHT 384 REFLECTION OF LIGHT 388 REFRACTION 397 DOUBLE REFRACTION AND POLARISATION 399 CAUSE OF LIGHT AND COLOUR 408 THE SPECTROSCOPE 416 CELESTIAL CHEMISTRY AND PHYSICS 436 ROENTGEN’S X RAYS 445 SIGHT 452 THE EYE 454 VISUAL IMPRESSIONS 468 ELECTRICITY 481 ELEMENTARY PHENOMENA OF ELECTRICITY AND MAGNETISM 483 THEORY OF ELECTRICITY 487 ELECTRIC INDUCTION 488 DYNAMICAL ELECTRICITY 490 INDUCED CURRENTS 502 MAGNETO-ELECTRICITY 507 THE GRAMME MAGNETO-ELECTRIC MACHINE 511 ELECTRIC LIGHTING AND ELECTRIC POWER 519 THE NEW ELECTRICITY 538 THE ELECTRIC TELEGRAPH 547 TELEGRAPHIC INSTRUMENTS 553 TELEGRAPHIC LINES 572 THE TELEPHONE 581 LIGHTHOUSES 593 PHOTOGRAPHY 607 PHOTOGRAPHY IN COLOURS 630 PRINTING PROCESSES 632 STEREOTYPING 632 LITHOGRAPHY 636 OTHER PROCESSES 640 THE LINOTYPE MACHINE 645 RECORDING INSTRUMENTS 653 THE PHONOGRAPH 665 AQUARIA 675 THE CRYSTAL PALACE AQUARIUM 677 THE BRIGHTON AQUARIUM 682