"That's the correct term for a bearing that gets so hot it won't let the shaft or axle turn. Maybe you didn't know that!" "Well, Great Jumpin' Catfishes!" gasped Jimmie. "It's a good thing Ned isn't here to listen to that slang!" declared Harry. "As leader of the Wolf Patrol, Ned objects to slang!" "Well, if 'Catfishes' is any more slang than 'Frozen Hot Boxes,'" stoutly decided Jimmie, "I'll quit for keeps. Besides," he continued, "it's a good thing Ned isn't here or he'd laugh at us for a lot of amateurs who don't know how to run a motorcycle yet. I guess 'Yes'!" "Look here!" cried Jack in an excited voice. Then instantly glancing about as if afraid of being overheard he continued in a lower tone: "This looks to me like a sure case of someone's[Pg 11] having planned that we should have trouble. Feel the grit in that oil cup!" [Pg 11] "Let me see," urged Jimmie, stepping forward to bend over the machine for a careful exploration of the hot oil cup. Presently he straightened, and with wide open eyes glanced in wonderment toward his comrades as he extended a greasy forefinger for examination. "That's emery!" he choked. "Emery will cut any bearing!" "Emery!" echoed the two Black Bears in chorus. "Yes, sir, emery! Some one must have put it there meaning to bring disaster to us. Tell you what," Jimmie went on hurriedly in a hushed voice, "it looks as if somebody had it in for us and we are due to go through the old story of having difficulties just before we reach a stage of success! Someone's trying to delay the Grey Eagle!" "Let's not mind that just now," urged Jack, "the thing to do is to get this machine off the road and then hasten as fast as we can to the Black Bear Club Rooms to meet Ned. It's only two or three blocks to French Pierre's machine shop. One of you can tow me over[Pg 12] there and we'll leave all three machines with him for the day at least." [Pg 12] "Right-O!" answered Jimmie springing to his motorcycle and starting the engine. "I'll tow you as fast as you can ride!" In a few moments the three boys were again under way, but this time their progress was decidedly slower. Their course was laid toward a portion of the village devoted to factories. Here was located the