William Perry said this quote

“ The mechanism of the clock was enclosed in a box resembling a large cupboard, but I was disappointed with the workings. They were much smaller than I had anticipated. The clock was worked by heavy weights suspended on long cables. My father picked up a handle like the crank handle of a car and wound them up. There were two of them. One to work the hands, the other controlling the hammer which struck out the hours on a large bell. Then the mousetraps were set, Not to catch mice, but to control the lighting. Previously my father had to make a special trip each evening to switch on the lights of the clock, returning near midnight to switch them off. To obviate this he invented a method of light control which may have been unique. Two switches, one for switching on and the other for switching off were used. They were fixed on the inside wall of the tower. A mousetrap mounted near each switch was so arranged that when the trap sprung, the arc traversed by the closing trap enabled the switch to be flicked on or off as required. Adjustable sleeves were set along the the cables for required times. The sleeves on the descending cables tripped the mouse traps which actuated the switches. ”