il you have
spanned the thousand horizons that lie between England and America. The
mind, that is to say, works in steps and spans corresponding to the spans
of physical sight; it cannot clear itself enough from the body, or rise
high enough beyond experience, to comprehend spaces so much vaster than
anything ever seen by the eye of man. So also with the stretching of the
horizon which bounded human knowledge of the earth. It moved step by
step; if one of Prince Henry's captains, creeping down the west coast of
Africa, discovered a cape a hundred miles south of the known world, the
most he could probably do was to imagine that there might lie, still
another hundred miles farther south, another cape; to sail for it in
faith and hope, to find it, and to imagine another possibility yet
another hundred miles away. So far as experience went back, faith could
look forward. It is thus with the common run of mankind; yesterday's
march is the measure of to-morrow's; as much as they have done once, they
may do again; they fear it will be not much more; they hope it may be not
much less.

The history of the exploration of the world up to the day when Columbus
set sail from Palos is just such a history of steps. The Phoenicians
coasting from harbour to harbour through the Mediterranean; the Romans
marching from camp to camp, from country to country; the Jutes venturing
in their frail craft into the stormy northern seas, making voyages a
little longer and more daring every time, until they reached England; the
captains of Prince Henry of Portugal feeling their way from voyage to
voyage down the coast of Africa--there are no bold flights into the
incredible here, but patient and business-like progress from one
stepping-stone to another. Dangers and hardships there were, and brave
followings of the faint will-o'-the-wisp of faith in what lay beyond; but
there were no great launchings into space. They but followed a line that
was the continuance or projection of the line they had hitherto followed;
what they did was brave and glorious, but it was reasonable. What
Columbus did, on the contrary, was, as we shall see later, against all
reason and knowledge. It was a leap in the dark towards some star
invisible to all but him; for he who sets forth across the desert sand or
sea must have a brighter sun to guide him than that which sets and rises
on the day of the small man.

Our familiarity with maps and atlases makes it diffi