 When the surfaces of the canes just begin to melt, the canes adhere to each other.The tip of a glassblowing pipe (blowpipe) is covered with a 'collar' of clear molten glass, and touched to one corner of the aligned canes.The tip of the blowpipe is then rolled along the bottom of the canes, which stick to the collar, aligned cylindrically around the edge of the blowpipe.