APPENDIX I ACCOUNTS OF EARLY WRITERS, NAVIGATORS AND OTHERS, ALLUDED TO IN GILBERT’S _DE MAGNETE_ 501 “THE SCHOOL OF ATHENS” 542 APPENDIX II DISCOVERIES MADE BY WILLIAM GILBERT (DESIGNATED IN _DE MAGNETE_ BY LARGE ASTERISKS) 545 APPENDIX III HISTORICAL ACCOUNT OF THE UNABRIDGED AND ABRIDGED EDITIONS OF THE ROYAL SOCIETY “PHILOSOPHICAL TRANSACTIONS”; ALSO, OF THE “PHILOSOPHICAL MAGAZINE” AND OF THE “JOURNAL DES SÇAVANS--SAVANTS” 547 APPENDIX IV NAMES OF ADDITIONAL ELECTRICAL AND MAGNETICAL WORKS, PUBLISHED UP TO 1800 553 APPENDIX V MERCATOR’S PROJECTION 559 GENERAL INDEX OF SELECTED AUTHORS AND SUBJECTS 565 LIST OF ILLUSTRATIONS ST. AUGUSTINE _Frontispiece_ “La Cité de Dieu, translatée et exposée par Raoul de Presles.” Taken from the manuscript in the Musée de Chantilly, by permission of the executors of Monsieur le Duc d’Aumale. _Facing page_ CAIUS PLINIUS SECUNDUS 11 Page taken from the earliest known edition of the “Naturalis Historiae” Venetiis, 1469, of which there are only three known original vellum copies. These now are at Vienna, Ravenna and in the Bibliothèque Sainte Geneviève, Paris. ARISTOTLE 11 “De Naturali Auscultatione.” Title-page of the Paris 1542 edition. This belonged to Dr. William Gilberd, when at Cambridge, and is inscribed with his name and with that of Archdeacon Thomas Drant. (From the library of the late Silvanus P. Thompson). GUIOT DE PROVINS 30 “La Bible.” Page 93 _verso_ of MS. Fr., No. 25405, _Variorum Poëmata_, in the Bibliothèque Nationale, Paris. VINCENT DE BEAUVAIS 33 “Speculum Naturale.” Page taken from the (Argentorati) 1473 issue, _la première édition et la plus rare de toutes_. In the Bibliothèque Sainte Geneviève, Paris. BRUNETTO LATINI 43 “Li Livres dou Trésor.” Page taken from the XVth Century MS. (originally copied by Jean du Quesne), No. 191, _Trésor de Sapience_, in the Bibliothèque Nationale, Paris. DANTE ALIGHIERI 44