meant the kingdom of Prester John, that fabulous monarch who had been the subject of persistent legends since the twelfth century; and it was this India to which the Portuguese sought a sea road.  They had no idea of a barrier cape far to the south, the doubling of which would open a road for them to the west; nor were they, as Mr. Vignaud believes, trying to open a route for the spice trade with the Orient.  They had no great spice trade, and did not seek more; what they did seek was an extension of their ordinary trade with Guinea and the African coast.  To the maritime world of the fifteenth century, then, the South as a geographical region and as a possible point of discovery had no attractions.

To the west stretched what was known as the Sea of Darkness, about which even the cool knowledge of the geographers and astronomers could not think steadily.  Nothing was known about it, it did not lead anywhere, there were no people there, there was no trade in that direction.  The tides of history and of life avoided it; only now and then some terrified mariner, blown far out of his course, came back with tales of sea monsters and enchanted disappearing islands, and shores that receded, and coasts upon which no one could make a landfall.  The farthest land known to the west was the Azores; beyond that stretched a vague and impossible ocean of terror and darkness, of which the Arabian writer Xerif al Edrisi, whose countrymen were the sea-kings of the Middle Ages, wrote as follows: 

“The ocean encircles the ultimate bounds of the inhabited earth, and all beyond it is unknown.  No one has been able to verify anything concerning it, on account of its difficult and perilous navigation, its great obscurity, its profound depth, and frequent tempests; through fear of its mighty fishes and its haughty winds; yet there are many islands in it, some peopled, others uninhabited.  There is no mariner who dares to enter into its deep waters; or if any have done so, they have merely kept along its coasts, fearful of departing from them.  The waves of this ocean, although they roll as high as mountains, yet maintain themselves without breaking; for if they broke it would be impossible for a ship to plough them.”

It is another illustration of the way in which discovery and imagination had hitherto gone by steps and not by flights, that geographical knowledge reached the islands of the Atlantic (none of which were at a very great distance from the coast of Europe or from each other) at a comparatively early date, and stopped there until in Columbus there was found a man with faith strong enough to make the long flight beyond them to the unknown West.  And yet the philosophers, and later the cartographers, true to their instinct for this pedestrian kind of imagination, put mythical lands and islands to the westward of the known islands as though they were really trying to make a way, to sink stepping stones into the deep sea that would