"Deziame a mi vn piloto muy diestro Portugues [~q] eran quatro puntos en todo el orbe, donde se afixaua el aguja con el Norte, y contaualas por sus nombres, de que no me acuerdo bien. Vno destos es el paraje de la Isla del Cueruo, en las Terceras, o Islas de Açores, como es cosa y a muy sabida. Passando di alli a mas altura, Noruestea, que es dezir, [~q] declina al Poniente ... que me digã la causa desta efecto?... Porque vn poco de hierro de fregarse cõ la piedra Iman ... "Mejor es, como dize Gregorio Theologo, que a la Fe se sujete la razon, pues aun en su casa no sabe bien entenderse...." [30] PAGE 5, LINE 36. Page 5, line 45. _Livius Sanutus._--Livio Sanuto publisht at Venice in 1588 a folio work, _Geografia distinta in xii Libri; ne' quali, oltre l'esplicatione di nostri luoghi di Tolomeo, della Bussola e dell' Aguglia, si dichiarono le provincie ... dell' Africa_. In this work all Liber i. (pages 1-13) deals with observations of the compass, mentioning Sebastian Cabot, and other navigators. He gives a map of Africa, showing the central lakes out of which flow the _Zaires fluvius_ and the _Zanberes fluvius_. [31] PAGE 6, LINE 2. Page 6, line 5. _Fortunius Affaitatus._--The work of Affaytatus, _Physicæ ac astronomiæ considerationes_, was publisht in Venice in 1549. [32] PAGE 6, LINE 3. Page 6, line 6. _Baptista Porta._--The reference is to his celebrated _Magia naturalis_, the first edition of which came out in 1558 at Naples. An English edition, _Natural Magick by John Baptista Porta, a Neapolitaine_, was printed in London, 1658. Book seven of this volume treats "Of the wonders of the Load-stone." In the proem to this book Porta says: "I knew at Venice R. M. Paulus, the Venetian, that was busied in the same study: he was Provincial of the Order of servants, but now a most worthy Advocate, from whom I not only confess, that I gained something, but I glory in it, because of all the men I ever saw, I never saw any man more learned, or more ingenious, having obtained the whole body of learning; and is not only the Splendor and Ornament of Venice or Italy, but of the whole world." The reference is to Fra Paolo Sarpi, better known as the historian of the Council of Trent. Sarpi was himself known to Gilbert. {17} His relations with Gilbert are set forth in the memoir prefixt to the edition of his works, _Opere di Fra Paolo Sarpi, Servita_ ... in Helmstat, MDCCLXI, p. 83. "Fino a questi giorni continuava il Sarpi a raccorre osservazioni sulla declinazione dell' Ago Calamitato; e poi ch' egli, atteso il variare di tal declinazione, assurdità alcuna non trovava riguardo al pensamento dell' Inglese Guglielmo Gilberto, cioè, che l'interno del nostro Globo fosse gran Calamita...." Here follows a quotation from a letter of Sarpi to Lescasserio: