It had not taken the Rover boys long to discover that not only the dictatorial old teacher, but also the bully, Dan Baxter, were rascals, and, what was more, that Arnold Baxter, the father of Dan, was an old enemy to their father. Following this had come a journey to Africa and into the jungle in search of Mr. Rover, and this mission accomplished, the Rover boys had gone West to establish a mining claim in which their father was interested. This claim was disputed by the Baxters, and when the Rovers won out and went for a pleasure trip on the Great Lakes, the Baxters did their best to bring Dick, Tom, and Sam to grief. But instead of accomplishing their purpose they failed once more, and Arnold Baxter was returned to the prison from which he had escaped some months before. What had become of Dan Baxter nobody knew, but the Rover boys were soon to learn, as we will see in the chapters which follow. After their stirring adventures on the Great Lakes, and especially on Needle Point Island in Lake Huron, the Rover boys were glad enough to get back to dear old Putnam Hall and to their studies, even though the latter were something of a "grind," as Tom declared. They all loved Captain Victor Putnam, the owner of the institution, and it may be added here that the captain thought as much of the Rovers as he did of any of the scholars under him, and that was a good deal. The coming of Jasper Grinder as a new under-teacher was a shock to many of the boys at the school. The principal teacher under Captain Putnam was Professor George Strong, who was stern but fair, and almost as well liked as the captain himself, and there were now several others, all of whom were on a good footing with the scholars. What had induced the captain to take in such a dictatorial and harsh master as Jasper Grinder was a mystery which nobody could explain. As a matter of fact, Grinder had come into the Hall under a misrepresentation. He was from the Northwest, and claimed to have been a professor at a well-known California college. It was true he had once taught at this college, but his record was far from being as satisfactory as Captain Putnam had been led to believe. It was true he was a learned man,--quite the opposite of Josiah Crabtree, who had been wise only in looks,--but it was also true that he was a high-strung, passionate man, given to strange fits of anger, and that he was a miser, never spending a cent that was not absolutely required of him. "I say, let me go!" cried Sam, as Jasper Grinder almost dragged him across the parade ground between the gymnasium and the school building. "I am not to blame for this row." "Silence! I won't listen to a word until we are in the office," commanded the irate teacher. "He started the whole thing," came from Tubbs. "He called me Tubby, and got the crowd to singing a song about me." "I had nothing to do with the song, and all the boys have called you Tubby since you came here," went on Sam.