Fun fact.. Those clamps on the lift cable holding that metal bucket which suspends you sometimes a hundred feet above rocky cliffs.. Well, they aren't clamped ALL the way down on the cable as tightly as most people think, They are set to a particular torque which allows them to start sliding down the cable if they hit something solid.. Those white marks are to show where they were initially clamped at the beginning of the season.. If they rattle too far down the cable past the mark that is a clue to check the torque..
See how these chairs stacked up when one got stuck somehow? This was NOT a detachable chairlift.. First one jammed at the previous tower and the next four got pushed in to eachother as their claws allowed the cable to slide along instead of snapping the whole cable. That was how the equipment was supposed to work when a chair jams at a tower like that..
http://abcnews.go.com/GMA/video/chairlifts-collide-ski-lift-malfunction-injuring-51843323