Of course, where there is so much fighting, the students make it a point to keep themselves in constant practice with the foil. One often sees them, at the tables in the Castle grounds, using their whips or canes to illustrate some new sword trick which they have heard about; and between the duels, on the day whose history I have been writing, the swords were not always idle; every now and then we heard a succession of the keen hissing sounds which the sword makes when it is being put through its paces in the air, and this informed us that a student was practicing. Necessarily, this unceasing attention to the art develops an expert occasionally. He becomes famous in his own university, his renown spreads to other universities. He is invited to Goettingen, to fight with a Goettingen expert; if he is victorious, he will be invited to other colleges, or those colleges will send their experts to him. Americans and Englishmen often join one or another of the five corps. A year or two ago, the principal Heidelberg expert was a big Kentuckian; he was invited to the various universities and left a wake of victory behind him all about Germany; but at last a little student in Strasburg defeated him. There was formerly a student in Heidelberg who had picked up somewhere and mastered a peculiar trick of cutting up under instead of cleaving down from above. While the trick lasted he won in sixteen successive duels in his university; but by that time observers had discovered what his charm was, and how to break it, therefore his championship ceased. A rule which forbids social intercourse between members of different corps is strict. In the dueling-house, in the parks, on the street, and anywhere and everywhere that the students go, caps of a color group themselves together. If all the tables in a public garden were crowded but one, and that one had two red-cap students at it and ten vacant places, the yellow-caps, the blue-caps, the white caps, and the green caps, seeking seats, would go by that table and not seem to see it, nor seem to be aware that there was such a table in the grounds. The student by whose courtesy we had been enabled to visit the dueling-place, wore the white cap--Prussian Corps. He introduced us to many white caps, but to none of another color. The corps etiquette extended even to us, who were strangers, and required us to group with the white corps only, and speak only with the white corps, while we were their guests, and keep aloof from the caps of the other colors. Once I wished to examine some of the swords, but an American student said, "It would not be quite polite; these now in the windows all have red hilts or blue; they will bring in some with white hilts presently, and those you can handle freely." When a sword was broken in the first duel, I wanted a piece of it; but its hilt was the wrong color, so it was considered best and politest to await a properer season.