It would seem that the steam itself is not produced by heatin’ water by anythin’ as wasteful as fire, but by puttin’ the fluid under intense pressure which in turn seems to create enough energy to power the vapour through the systems and out to create the clouds. This lends a lot to the thrust of the vessel itself, although the height maintenance is achieved by means of a variable magnetic force that repels the city from the planets core. This of course has to adjust accordin’ to the latitude of your coordinates or you would find yourself dragged to the bottom of the ocean at an alarmin’ rate.
It occurred to me that in my distraction, I had not been payin’ any heed at all to such things as wind speed velocity or direction, and as I had not thought to attempt any form of affective navigation of Crank City, I had been driftin’ blindly for several days. Satisfied that I had averted any imminent disaster involvin’ the city rustin’ and plummetin’ to its doom, I decided to spend the evenin’ studyin’ the techniques involved in its manoeuvre and tomorrow I shall have to dip below the clouds in an attempt to regain an impression of where I am.