Old chain ferry mechanism

I was at a meeting in the historic old parish of Govan in Glasgow today. Chances are no matter where in the world you are reading this blip you'll have a Govan-built ship not too far from you. 

This is the old mechanism for the car and passenger ferry across the Clyde from Govan to Partick. Turns out there were many of these in the hey-day of the shipyards. They dragged the ferry over the Clyde using steam power and chains on the river bed.

As you look at it, the Clyde drops steeply to the right of the view and the Partick side is in close view. The ferry must have taken all of two minutes to cross the water.