The Power Hall is packed full of beautifully maintained engines, all themed around water.
Each engine was originally used to move water or drive things through it; or used water (hydraulic engines), or steam to drive boat engines.
The engines are looked after by museum volunteers. If they are on duty when you visit (look for the men in the overalls!), they will be happy to talk to you about their work.
The Yarwood steam engine. This engine used to power the Weaver packet boat Davenham on her regular travels bringing soda ash from Winnington Works to Birkenhead or Liverpool for chemical company ICI. Dagenham's journey used to take her down the Weaver Navigation, onto the Manchester Ship Canal and then to the River Mersey.
Today you can power up her Yarwood engine though she won't be going anywhere!
I will attempt to get an image of Yarwood on my next visit; for now, here are a few which I do have.