Stephenson's Rocket (Replica) and Black 5 Steam Locomotive (No. 5000). I had the pleasure of meeting two gentlemen that discussed the workings and specifications of the two locomotives. The first video discusses Stephenson's Rocket (Replica) and the second discusses Black Five (No. 5000) steam locomotive

Website for more info: https://www.locomotion.org.uk/

Chapter timestamps:

00:00 Video One
00:22 Stephenson's Rocket (Replica)
05:25 Video Two
05:35 Black Five (No. 5000)