A surgical system includes a first instrument defining a first channel and a second instrument receivable by the first channel. The printer heats untreated withdrawn vapors with heat from the vapor treatment system. The window panel includes a flexible area and a rigid area provided adjacent to at least one side of the flexible area. A method is provided for probing, dissecting, and retracting anatomical structures. Thus, the cooling water flows through the water inlet hole of the water inlet port into the gathering portion of the base to surround the drill bit so as to provide a cooling effect to the drill bit and the workpiece during the drilling process. A p-stage shift register which is clocked at a clock frequency corresponding to the high clock frequency of the digital circuit to be tested has connected to its parallel loading inputs p logical gates which logically combine a static control word with a dynamic n-position test word.