One does not wonder that they did not see ahead of them--men never do.

One does rather wonder that they did not see what was before their eyes.

But wonder is useless and a mistake.

People who have never seen a volcano cannot be expected to fear the burning lava, or even to see that a volcano differs from any other mountain.
Gibbon had brought good introductions from London, but he admits that they were useless, or rather superfluous.

His nationality and his _Essai_ were his best recommendations.