It's a tandem compound with low presure cylinder in front of high pressure cylinder. It therefore has a single crank rather than double crank where cylinders are set out side by side. The exception being Burrell single crank compounds where cylinders arranged diagonally using a common cross head and single crank.

The engine is a McLaren resconstructed by John Atkinson from parts imported from some far off country I believe.

See here:

http://www.tractiontalkforum.com/showthread.php?t=19118

It was a treat to see; beautifully original and with great history too.

Thank you
 

Many thanks David.
Looks like a lovely engine, would make a fine miniature.

Nick

Edited for accuracy :p

It is indeed a fantastic beast engine though, according a friend of mine lucky enough to have steered it

Was that you wearing the bowler on Sat night Brian?

Re. the last photo, I'll have to get one of those signs for my caravan!