"When we have discovered a continent, or crossed a chain of mountains, it is only to find another ocean or another plain upon the further side. . . . O toiling hands of mortals! O wearied feet, travelling ye know not whither! Soon, soon, it seems to you, you must come forth on some conspicuous hilltop, and but a little way further, against the setting sun, descry the spires of El Dorado. Little do ye know your own blessedness; for to travel hopefully is a better thing than to arrive, and the true success is to labour."