[20] PAGE 5, LINE 8. Page 5, line 11. _Petri cujusdam Peregrini_.--This opusculum is the famous letter of Peter Peregrinus written in 1269, of which some twenty manuscript copies exist in various libraries in Oxford, Rome, Paris, etc., and of which the oldest printed edition is that of 1558 (Augsburg). See also Libri, _Histoire des Sciences Mathématiques_ (1838); Bertelli in Boncompagni's _Bull. d. Bibliogr._ T. I. and T. IV. (1868 and 1871), and Hellmann's _Rara Magnetica_ (1898). A summary of the contents of Peregrinus's book will be found in Park Benjamin's _Intellectual Rise in Electricity_ (1895), pp. 164-185.
[21] PAGE 5, LINE 12. Page 5, line 15. _Johannes Taisner Hannonius._--Taisnier, or Taysnier, of Hainault, was a plagiarist who took most of the treatise of Peregrinus and publisht it in his _Opusculum... de Natura Magnetis_ (Coloniæ, 1562), of which an English translation by Richard Eden was printed by R. Jugge in 1579.
[22] PAGE 5, LINE 18. Page 5, line 23. _Collegium Conimbricense_.--This is a reference to the commentaries on Aristotle by the Jesuits of Coimbra. The work is _Colegio de Coimbra da Companhia de Jesu, Cursus Conimbricensis in Octo libros Physicorum_ (Coloniæ, sumptibus Lazari Ratzneri, 1599). Other editions: Lugd. 1594; and Colon., 1596. The later edition of 1609, in the British Museum, has the title _Commentariorum Collegii Conimbricensis in octo libros physicorum_.
[23] PAGE 5, LINE 25. Page 5, line 31. _Martinus Cortesius_.--His _Arte de Navegar_ (Sevilla, 1556) went through various editions in Spanish, Italian, and English. Eden's translation was publisht 1561, and again in 1609.
[24] PAGE 5, LINE 26. Page 5, line 33. _Bessardus_.--Toussaincte de Bessard wrote a treatise, _Dialogue de la Longitude_ (Rouen, 1574), which gives some useful notes of nautical practice, and of the French construction of the compass. Speaking of the needle he says: "Elle ne tire pas au pole du monde: ains regarde, au Pole du Zodiaque, comme il sera discoursu, cy apres" (p. 34). On p. 50 he speaks of "l'aiguille Aymantine." On p. 108 he refers to Mercator's _Carte Générale_, and denies the existence of the alleged loadstone rock. On p. 15 he gives the most naïve etymologies for the terms used: thus he assigns as the derivation of _Sud_ the Latin _sudor_, because the south is hot, and as that of _Ouest_ that it comes from _Ou_ and _Est_. "Come, qui diroit, Ou est-il? à scauoir le Soleil, qui estoit nagueres sur la terre."