Hi guys. I just found this model on the internet. It did really interested me. It was designed from some workings drawings found a website in which you can buy a modern plastic veion of this machine (many websites like Amazon or Superhobby.com have this models available to the public). About this machine, Leonardo's clock has two separate mechanisms: one for minutes and one for hou. Each was made up of elaborately connected weights, gea and harnesses. In this modern veion of the clock, you could adjust the speed of the clock by adding or removing coi from the weight of the suspeion. Altough the original veión may have used some small disc with lead or some metal.I hope you like it. Thanks.