Footnote 462: The reader will also notice upon Toscanelli's map the islands of Brazil and St. Brandan. For an account of all these fabulous islands see Winsor, Narr. and Crit. Hist., vol. i. pp. 46-51. The name of "Antilia" survives in the name "Antilles," applied since about 1502 to the West India islands. All the islands west of Toscanelli's ninetieth meridian belong in the Pacific. He drew them from his understanding of the descriptions of Marco Polo, Friar Odoric, and other travellers. These were the islands supposed, rightly, though vaguely, to abound in spices.[Back to Main Text]
Footnote 463: Columbus was confirmed in this opinion by the book of the Arabian astronomer Alfragan, written about A. D. 950, a Latin translation of which appeared in 1447. There is a concise summary of it in Delambre, Histoire de l'astronomie du Moyen Âge, pp. 63-73. Columbus proceeded throughout on the assumption that the length of a degree at the equator is 56.6 geographical miles, instead of the correct figure 60. This would oblige him to reduce all Toscanelli's figures by about six per cent., to begin with. Upon this point we have the highest authority, that of Columbus himself, in an autograph marginal note in his copy of the Imago Mundi, where he expresses himself most explicitly: "Nota quod sepius navigando ex Ulixbona ad Austrum in Guineam, notavi cum diligentia viam, ut solitum naucleris et malineriis, et preteria accepi altitudinem solis cum quadrante et aliis instrumentis plures vices, et inveni concordare cum Alfragano, videlicet respondere quemlibet gradum milliariis 56-2/3. Quare ad hanc mensuram fidem adhibendam. Tunc igitur possumus dicere quod circuitus Terræ sub aræ equinoctiali est 20,400 milliariorum. Similiter que id invenit magister Josephus phisicus et astrologus et alii plures missi specialiter ad hoc per serenissimum regem Portugaliæ," etc.; anglicè, "Observe that in sailing often from Lisbon southward to Guinea, I carefully marked the course, according to the custom of skippers and mariners, and moreover I took the sun's altitude several times with a quadrant and other instruments, and in agreement with Alfragan I found that each degree [i. e. of longitude, measured on a great circle] answers to 56-2/3 miles. So that one may rely upon this measure. We may therefore say that the equatorial circumference of the earth is 20,400 miles. A similar result was obtained by Master Joseph, the physicist [or, perhaps, physician] and astronomer, and several others sent for this special purpose by the most gracious king of Portugal."—Master Joseph was physician to John II. of Portugal, and was associated with Martin Behaim in the invention of an improved astrolabe which greatly facilitated ocean navigation.—The exact agreement with Ptolemy's figures shows that by a mile Columbus meant a geographical mile, equivalent to ten Greek stadia.[Back to Main Text]
Footnote 464: One seventh of 18,000 is 2,571 geographical miles, equivalent to 2,963 English miles. The actual length of Columbus's first voyage, from last sight of land in the Canaries to first sight of land in the Bahamas, was according to his own dead reckoning about 3,230 geographical miles. See his journal in Navarrete, Coleccion, tom. i. pp. 6-20.
I give here in parallel columns the passage from Bacon and the one from Alliacus upon which Columbus placed so much reliance. In the Middle Ages there was a generous tolerance of much that we have since learned to stigmatize as plagiarism.
| From Roger Bacon, Opus | From Petrus Alliacus, De |
| Majus (A. D. 1267), London, | imagine Mundi (A. D. 1410), |
| 1733, ed. Jebb, p. 183:—"Sed | Paris, cir. 1490, cap. viii. fol. |
| Aristoteles vult in fine secundi | 13 b:—"Summus Aristoteles |
| Cœli et Mundi quod plus [terræ] | dicit quod mare parvum est inter |
| habitetur quam quarta pars. Et | finem Hispaniæ a parte occidentis |
| Averroes hoc confirmat. Dicit | et inter principium Indiæ |
| Aristoteles quod mare parvum | a parte orientis, et vult quod |
| est inter finem Hispaniæ a parte | plus habitetur quam quarta |
| occidentis et inter principium | pars, et Averroes hoc confirmat. |
| Indiæ a parte orientis. Et Seneca, | Insuper Seneca libro |
| libro quinto Naturalium, | quinto Naturalium, dicit quod |
| dicit quod mare hoc est navigabile | mare est navigabile in paucis |
| in paucissimis diebus si | diebus si ventus sit conveniens. |
| ventus sit conveniens. Et Plinius | Et Plinius docet in Naturalibus, |
| docet in Naturalibus quod | libro secundo, quod navigatum |
| navigatum est a sinu Arabico | est a sinu Arabico usque ad |
| usque ad Gades: unde refert | Gades Herculis non multum |
| quendam fugisse a rego suo | magno tempore, |
| præ timore et intravit sinum | |
| Maris Rubri ... qui circiter | |
| spatium navigationis annualis | |
| distat a Mari Indico: ... ex | |
| quo patet principium Indiæ in | |
| oriente multum a nobis distare | |
| et ab Hispania, postquam tantum | |
| distat a principio Arabiæ | |
| versus Indiam. A fine Hispaniæ | unde concludunt |
| sub terra tam parvum mare est | aliqui, quod mare non est |
| quod non potest cooperire tres | tantum quod possit cooperire |
| quartas terræ. Et hoc per | tres quartas terræ. Accedit ad |
| auctoritatem alterius considerationis | hoc auctoritas Esdræ libro suo |
| probatur. Nam Esdras | quarto, dicentis quod sex partes |
| dicit quarto libro, quod sex | |
| partes terræ sunt habitatæ et | terrae sunt habitatæ et septima |
| septima est cooperta aquis. Et | est cooperta aquis, |
| ne aliquis impediat hanc auctoritatem, | |
| dicens quod liber ille | |
| est apocryphus et ignotæ auctoritatis, | |
| dicendum est quod | cujus libri auctoritatem sancti |
| sancti habuerunt illum librum | habuerunt in reverentia." |
| in usu et confirmant veritates | |
| sacras per illum librum." |
Columbus must either have carried the book of Alliacus with him on his voyages, or else have read his favourite passages until he knew them by heart, as may be seen from the following passage of a letter, written from Hispaniola in 1498 to Ferdinand and Isabella (Navarrete, tom i. p. 261):—"El Aristotel dice que este mundo es pequeño y es el agua muy poca, y que facilmente se puede pasar de España à las Indias, y esto confirma el Avenryz [Averroes], y le alega el cardenal Pedro de Aliaco, autorizando este decir y aquel de Seneca, el qual conforma con estos.... À esto trac una autoridad de Esdras del tercero libro suyo, adonde dice que de siete partes del mundo las seis son descubiertas y la una es cubierta de agua, la cual autoridad es aprobada por Santos, los cuales dan autoridad al 3o é 4o libro de Esdras, ansí come es S. Agustin é S. Ambrosio en su exámeron," etc.—"Singular period," exclaims Humboldt, "when a mixture of testimonies from Aristotle and Averroes, Esdras and Seneca, on the small extent of the ocean compared with the magnitude of continental land, afforded to monarchs guarantees for the safety and expediency of costly enterprises!" Cosmos, tr. Sabine, vol. ii. p. 250. The passages cited in this note may be found in Humboldt, Examen critique, tom. i. pp. 65-69. Another interesting passage from Imago Mundi, cap. xv., is quoted on p. 78 of the same work.[Back to Main Text]
Footnote 465: See below, vol. ii. p. 96.[Back to Main Text]
Footnote 466: Vita dell' Ammiraglio, cap. iv.; Las Casas, Historia, tom. i. p. 49.[Back to Main Text]
Footnote 467: "Io navigai l' anno M CCCC LXXVII nel mese di Febraio oltra Tile isola cento leghe, la cui parte Australe è lontana dall' Equinottiale settantatrè gradi, e non sessantatrè, come alcuni vogliono; nè giace dentro della linea, che include l' Occidente di Tolomeo, ma è molto più Occidentale. Et a questa isola, che è tanto grande, come l'Inghilterra, vanno gl' Inglesi con le loro mercatantie, specialmente quelli di Bristol. Et al tempo che io vi andai, non era congelato il mare, quantunque vi fossero si grosse maree, che in alcuni luoghi ascendeva ventisei braccia, e discendeva altretanti in altezza. È bene il vero, che Tile, quella, di cui Tolomeo fa mentione, giace dove egli dice; & questa da' moderni è chiamata Frislanda." Vita dell' Ammiraglio, cap. iv. In the original edition of 1571, there are no quotation-marks; and in some modern editions, where these are supplied, the quotation is wrongly made to end just before the last sentence, so as to make it appear like a gloss of Ferdinand's. This is, however, impossible. Ferdinand died in 1539, and the Zeno narrative of Frislanda was not published till 1558, so that the only source from which that name could have come into his book was his father's document. The genuineness of the passage is proved by its recurrence, almost word for word, in Las Casas, Historia, tom. i. p. 48.[Back to Main Text]
Footnote 468: See Thorold Rogers, The Economic Interpretation of History, London, 1888, pp. 103, 319.[Back to Main Text]