Just for fun, the D10 my dad gave me for my birthday in 1969 (my 1st bday) and the Ferris Wheel my brother gave me this year. I am told my Wilesco D10 is pretty special as it was only sold by Sears (since it has a regulator for stream control to the engine).
I was pleasantly surprised that the little D10 didn't have any problems running the Empire Ferris Wheel and with "riders" too :-D