One more instance I will give of his interest and his knowledge. We were passing under a fir tree when we heard a small song in the tree above us. We stopped and I said that was the song of a golden-crested wren. He listened very attentively while the bird repeated its little song, as its habit is. Then he said, 'I think that is exactly the same song as that of a bird that we have in America'; and that was the only English song that he recognized as being the same as any bird song in America. Some time afterwards I met a bird expert in the Natural History Museum in London and told him this incident, and he confirmed what Colonel Roosevelt had said, that the song of this bird would be about the only song that the two countries had in common. I think that a very remarkable instance of minute and accurate knowledge on the part of Colonel Roosevelt. It was the business of the bird expert in London to know about birds. Colonel Roosevelt's knowledge was a mere incident acquired, not as part of the work of his life, but entirely outside it.