All the other students turned furiously upon the solemn four and glared fiercely. One of the four opened his lips as if to say something, then thought better of it, and shut them again. "If you want to make a link in the mystic chain of the Pi Gamma," exclaimed the leader, sternly, "you'd better keep your mouth shut!" The student thus addressed looked as if he was aching to say that he had not said anything, but his eyes simply wavered and otherwise he remained perfectly still. "I guess they'll behave themselves," declared the leader. "Go out and bring in Merriwell." Frank was about to take his first step in the long and trying initiation into the secret society known as the Pi Gamma. These are the two Greek letters standing for P and G, respectively. What they mean is known only to the members of the order, but the society is generally known by an abbreviation of its initials. In this way, with the characteristic humor of college students, the order of Pi Gamma is generally known as the "Pig." So, too, members of the order are sometimes referred to as "Pigs." No one is supposed to take any offense at this, for, on the contrary, it is a mark of honor to be a member of the order, and if a man can say after he has graduated that he belonged to the "Pig," he makes it known that his social standing was very high. No one can become a member of this society until he has reached the junior year; then students are elected from the junior class by the members of the senior class in blocks of five. The initiation of each block of five covers a period of one week. The juniors elected at the same time with Frank were Harry Rattleton, Jack Diamond, Bartley Hodge, and John Henderson. It was these four who formed the quartet of silent students with their backs to the wall. They had received their notification of election on the evening before, and with it certain instructions. From that moment until the end of the initiation the neophyte was forbidden to laugh, or to speak aloud unless addressed by a "Pig" in good standing or a member of the faculty. If he was spoken to by one of his companions, not a member of the order, the neophyte was not to answer. He was to attend strictly to all his college duties, and whenever he set foot upon the campus, he was to run at full speed and not stop running until he had left the college grounds. He was to do without question anything commanded of him by any member of the Pi Gamma during the week. In Frank's case this last rule had been put to the test at once by commanding him to go to a well-known store in the city and buy one match and one toothpick and bring the articles to the student who asked for them. Frank had complied promptly. He went into this thing, as he did into everything, in a good-natured but businesslike way. He knew that it was the custom for students to be put in embarrassing situations during the initiation, and he made up his mind to stand his share of it without grumbling.