His was the faith of the discoverer, the imagination of the poet, the voice of the prophet.

But his was not the warrior's arm, the engineer's skill, the architect's creativeness.

"I only sound the clarion," he says, "but I enter not into the battle;" and with a Greek quotation very rare with him, he compares himself to one of Homer's peaceful heralds, [Greek: chairete kerukes, Dios angeloi ede kai andron].

Even he knew not the full greatness of his own enterprise.

He underrated the vastness and the subtlety of nature.