One was that the Mad Musician had had offices and a studio in the Colossus and was one of the first to move in. The other was that the Mad Musician took great delight in shattering glassware with notes of or vibrations from a violin. Nearly everyone knows that a glass tumbler can be shattered by the proper note sounded on a violin. The Mad Musician took delight in this trick. Jenks courted his acquaintance, and saw him shatter a row of glasses of different sizes by sounding different notes on his fiddle. The glasses crashed one after another like gelatine balls hit by the bullets of an expert rifleman. Then Jenks, the engineer who knew his mathematics, put two and two together. It made four, of course. "Listen, Linane," he said to his co-worker: "this fiddler is crazier than a flock of cuckoos. If he can crack crockery with violin sound vibrations, is it not possible, by carrying the vibrations to a much higher power, that he could crack a pile of stone, steel, brick and cement, like the Colossus?" "Possible, but hardly probable. Still," Linane mused, "when you think about it, and put two and two together.... Let's go after him and see what he is doing now." Both jumped for their coats and hats. As they fared forth, Jenks cinched his argument: "If a madman takes delight in breaking glassware with a vibratory wave or vibration, how much more of a thrill would he get by crashing a mountain?" "Wild, but unanswerable," said Linane. * * * * * Jenks had been calling on the Mad Musician at his country place. "He had a studio in the Colossus," he reminded Linane. "He must have re-opened somewhere else in town. I wonder where." "Musicians are great union men," said Linane. "Phone the union." Teddy Jenks did, but the union gave the last known town address as the Colossus. "He would remain in the same district around Times Square," reasoned Jenks. "Let's page out the big buildings and see if he is not preparing to crash another one." "Fair enough," said Linane, who was too busy with the problem at hand to choose his words. Together the engineers started a canvass of the big buildings in the theatrical district. After four or five had been searched without result they entered the 30-story Acme Theater building. Here they learned that the Mad Musician had leased a four-room suite just a few days before. This suite was on the fifteenth floor, just half way up in the big structure. They went to the manager of the building and frankly stated their suspicions. "We want to enter that suite when the tenant is not there," they explained, "and we want him forestalled from entering while we are examining the premises." "Hadn't we better notify the police?" asked the building manager, who had broken out in a sweat when he heard the dire disaster which might be in store for the stately Acme building. "Not yet," said Linane. "You see, we are not sure: we have just been putting two and two together."