What you see in that picture is the fireman shoving the fuel oil to it to "make smoke" as most people think that is the way steam locomotives look when they are working hard, are coal fired and it makes a typical picture of what people expect to see. Or what they were taught to see when they were children by someone who didn't know any better. This is typicaly done on photo run bys. That is an expensive way to fire an oil fired steam locomotive as all that smoke is unburned fuel going up the stack and not making you BTU's. BTU's are the name of the game in steam locomotive operation. "A clean stack" indicates efficient firing and keeping most of those BTU critters boiling water for you not uselessly unburned fuel oil($$$)going up the stack.
:)