"It is some meestake," they heard him murmur. "Zis ees for Professor Grimm. I will take it to heem," and he walked along the corridor toward the elderly instructor's apartment. "Act one," whispered Sam. "Now for the second." Silently in their slippers the boys followed the French professor to Mr. Grimm's room. "What is it?" asked the latter when the Frenchman had knocked. "I come wiz a package, left by mistake wiz me," Mr. Socrat remarked, in his usual polite way. "It is addressed to you inside, but ze outside wrapper was wiz my name inscribed. I ask your pardon." "Thanks," said Mr. Grimm shortly, as, with a polite bow, Mr. Socrat went back to his room. Professor Grimm left his door open a little way, and the boys could see him quite plainly. They saw him take off the wrapper, and disclose a small white box. This he opened and, as he took the cover off, there dropped out something that gave a musical clang. "A bell!" exclaimed Jack in a whisper. "Hush!" cautioned Sam. "Let's hear what he says." "Ha!" exclaimed Mr. Grimm. "So this is a joke, eh, Mr. Frenchman? Well, we'll see about this!" He grasped the bell, which was a small one, by the handle, and started down the corridor, a scowl on his face, as the boys could see by a flickering gaslight, as they were hidden around the corner. "Now back to Mr. Socrat's room for the third act," said Sam. "Come on." Without the formality of a knock, Mr. Grimm entered the French teacher's room. "So this is your idea of a joke, eh?" he cried, shaking the bell under Professor Socrat's nose. "I'll report you to Dr. Mead for this. You frog-eater you!" "Sir-r-r-r!" fairly shouted Professor Socrat. "You call me a frog- eater-r-r-r-r?" "Yes, and a donkey also!" exclaimed Mr. Grimm. "You knew how I've felt since that bell joke, and you dare to send me a miniature one!" "I sent nossing!" "Didn't I see you just bring this?" demanded Mr. Grimm, holding out the bell. "It was addressed to you on ze paper!" "Yes, and you did it!" "I did not!" "I say you did!" "Zen you mean zat I tells a lie?" "If you want to take it that way!" "Zen I say you also are one who knows not ze truth!" "Don't call me that name or I'll--" What the excited professor meant to say was not disclosed as, at that moment, in shaking his fist at Professor Socrat he let slip the bell, which, with a clang struck the French teacher on the chest. "A blow! I am insult!" Mr. Socrat exclaimed. "It must be wiped out wiz ze blood of my insulter!" He caught up a book to throw at Mr. Grimm, and let it fly, just as Adrian Bagot entered the room. The sporty student caught it full in the face. "Pardon, my dear young friend!" exclaimed the French teacher, seeing his missile had gone wide of one mark, though finding another. "What does this mean?" demanded Adrian, as he saw the two belligerents. "Leave the room, sir!" ordered Professor Grimm. "This is none of your affair!" "I was asked to come here," said Adrian.