I find that when I am on horseback, going at a swinging gallop, a bright light affects me far more powerfully than when I am trudging along on foot. A person mounted on a bicycle and speeding over a level plain on a dark night, with nothing to guide him except the idea of the direction in his mind, would be to some extent in the position of the migratory bird. An exceptionally brilliant ignis fatuus flying before him would affect him as the gleam of a lamp placed high above the surface affects the migrants: he would not be able to keep his eyes from it, but would quickly lose the sense of direction, and probably end his career much as the bird does, by breaking his machine and perhaps his bones against some unseen obstruction in the way. CHAPTER XIV. FACTS AND THOUGHTS ABOUT SPIDERS. Some time ago, while turning over a quantity of rubbish in a little-used room, I disturbed a large black spider. Rushing forth, just in time to save itself from destruction through the capsizing of a pile of books, it paused for one moment, took a swift comprehensive glance at the position, then scuttled away across the floor, and was lost in an obscure corner of the room. This incident served to remind me of a fact I was nearly forgetting, that England is not a spiderless country. A foreigner, however intelligent, coming from warmer regions, might very easily make that mistake. In Buenos Ayres, the land of my nativity, earth teems with these interesting little creatures. They abound in and on the water, they swarm in the grass and herbage, which everywhere glistens with the silvery veil they spin over it. Indeed it is scarcely an exaggeration to say that there is an atmosphere of spiders, for they are always floating about invisible in the air; their filmy threads are unfelt when they fly against you; and often enough you are not even aware of the little arrested aeronaut hurrying over your face with feet lighter than the lightest thistledown.