This is a link to an animation of how the 3 crankshafts and 6 pistons of one bank on a Deltic engine work.
http://www.wis.co.uk/justin/deltic-engine.html
It is a fascinating design and as far as I am aware only used on the Deltics and "baby" Deltic railway locos. Otherwise it's main use was marine (boats).
For those who may be unaware,if you click your mouse on a link it will take you to another web page of interest. (I hope
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