The entrance to San Juan harbor is a difficult one and steamers must be piloted in with great care. But once inside there is a fine anchorage, two miles wide by three miles long, situated on the south side of the city. Along this shore are located the governor’s castle, the soldiers’ barracks, the custom house, and a large number of warehouses and other buildings. On the north side of the city is a finely-kept cemetery and also another soldiers’ barracks. “This city is really on an island,” said the professor, when they found themselves landed, the day after the talk above mentioned. “It is a long, narrow peninsula, separated from the mainland by a shallow body of water spanned by the San Antonio bridge. As you can see, it is inclosed by a high wall, which gives it the appearance of being what it really is, an old Spanish town. The castle you see on the bluff is Morro Castle, which played an important part during the War with Spain, just as did Morro Castle at Havana.” The streets were alive with people, and the boys were surprised to see how many were Americans. English signs were everywhere in evidence, and one reading, “Shooting Gallery, 3 Shots for 5 Cents,” made Darry laugh. “We are in an American town now for sure,” he observed. “You’d never see such a sign elsewhere.” “To be sure we are on United States soil,” cried Frank. “Hurrah for Porto Rico and its people!” He had scarcely spoken when a hack driver rushed up to them. “This way, gents!” he bawled. “Any hotel in the city. Take the six of you for a dollar! Best keb in the city!” “Well!” ejaculated Mark, stopping short. “That sounds as if we had struck the Grand Central Depot in New York.” “Oh, they are going to be up-to-date,” laughed the professor. “No, we may as well walk to the hotel and see the sights on the way,” he added, and shook his head at the cabman, and also at the crowd of native drivers who swarmed around them. “I see they have gas and telephones,” said Sam. “Yes, and also electric lights, Samuel--in fact they now have everything which you will find in any well-kept town in the States.” “But the streets are narrow,” put in Frank. “Only in the old part.” The houses were of stone and brick, painted various colors. The majority were of the old Spanish style of architecture, with small windows and flat roofs. Here and there was a new building, looking strangely out of place, with its wide windows and broad balconies. Professor Strong had a friend in the hotel business in San Juan, and to his place, called the Randall House, they made their way. It proved to be a comfortable hostelry, and they were assigned three spacious rooms on the second floor. From the roof of the hotel a splendid view of the entire city could be obtained, and here the boys spent some time, while the professor and the hotel proprietor pointed out various points of interest to them. CHAPTER XX AN ADVENTURE IN THE MOUNTAINS