Here's another quote using the word "leads":

The students of the sage's precepts, left to their own application of his wisdom upon a principle which was the main leg of the Bunsby tripod, as it is perchance of some other oracular stools--looked upon one another in a little uncertainty; while Rob the Grinder, who had taken the innocent freedom of peering in, and listening, through the skylight in the roof, came softly down from the leads...