He was a splendid example of the temperament that looks forward and not backward, and never wastes a moment in regrets for the irrevocable. I had the privilege of admission to his society during the Thayer expedition to Brazil. I well remember at night, as we all swung in our hammocks in the fairy-like moonlight, on the deck of the steamer that throbbed its way up the Amazon between the forests guarding the stream on either side, how he turned and whispered, "James, are you awake?" and continued, "_I_ cannot sleep; I am too happy; I keep thinking of these glorious plans." The plans contemplated following the Amazon to its headwaters, and penetrating the Andes in Peru. And yet, when he arrived at the Peruvian frontier and learned that that country had broken into revolution, that his letters to officials would be useless, and that that part of the project must be given up, although he was indeed bitterly chagrined and excited for part of an hour, when the hour had passed over it seemed as if he had quite forgotten the disappointment, so enthusiastically was he occupied already with the new scheme substituted by his active mind. Agassiz's influence on methods of teaching in our community was prompt and decisive,--all the more so that it struck people's imagination by its very excess. The good old way of committing printed abstractions to memory seems never to have received such a shock as it encountered at his hands. There is probably no public school teacher now in New England who will not tell you how Agassiz used to lock a student up in a room full of turtle shells, or lobster shells, or oyster shells, without a book or word to help him, and not let him out till he had discovered all the truths which the objects contained. Some found the truths after weeks and months of lonely sorrow; others never found them. Those who found them were already made into naturalists thereby--the failures were blotted from the book of honor and of life. "Go to Nature; take the facts into your own hands; look, and see for yourself!"--these were the maxims which Agassiz preached wherever he went, and their effect on pedagogy was electric. The extreme rigor of his devotion to this concrete method of learning was the natural consequence of his own peculiar type of intellect, in which the capacity for abstraction and causal reasoning and tracing chains of consequences from hypotheses was so much less developed than the genius for acquaintance with vast volumes of detail, and for seizing upon analogies and relations of the more proximate and concrete kind. While on the Thayer expedition, I remember that I often put questions to him about the facts of our new tropical habitat, but I doubt if he ever answered one of these questions of mine outright. He always said: "There, you see you have a definite problem; go and look and find the answer for yourself." His severity in this line was a living rebuke to