[Footnote 1: Carlos was a Spanish boy, who was residing at this time at the same hotel with Mr. George. The manner in which Rollo became acquainted with him is related in Rollo in Paris. Carlos did not understand English, nor Rollo Spanish; but when they were together they usually kept talking all the time, each in his own way.] [Footnote 2: A courier is a travelling servant and guide.] CHAPTER II. CROSSING THE FRONTIER. On the morning when Mr. George and Rollo were about setting out for Switzerland, Rollo, having got every thing ready himself half an hour before the time, took out his map of Europe and asked his uncle George what route they were going to take. Mr. George was busy at that time putting the last things into his trunk and making ready to lock it up and strap it; so he could not come to Rollo to show him the route, but was obliged to describe it. "Have you found Paris?" said he. "Yes," said Rollo; "I have got my finger on it." "In the first place, then," said Mr. George, "there is a railway that goes east from Paris a hundred miles across France to Strasbourg on the Rhine. See if you can find Strasbourg on the Rhine." "Yes," said Rollo; "here it is." "Then," said Mr. George, "we take another railway and go south, up the Rhine, towards Switzerland." "_Down_ the Rhine," said Rollo, correcting his uncle; "it is _down_." "No," rejoined Mr. George. "It is down on the map; that is, it is down the page; but it is really _up_ the river. The Rhine flows to the north. It collects the waters of a hundred glaciers in Switzerland and carries them north into the North Sea." "Well," said Rollo. "This railway," continued Mr. George, "will take us up from Strasbourg, along the bank of the Rhine, to Basle, which is in Switzerland, just across the frontier. It is there, I suppose, that we shall have to show our passports; and then we shall know if you got them stamped right." "I did get them stamped right, I am very sure," said Rollo. "Boys are generally very sure that what they do is done right," rejoined Mr. George. Soon after this Mr. George and Rollo took their seats in the carriage, which had been for some time standing ready for them in the court yard of the inn, and drove to the Strasbourg station.