Double-decker tram

I should like to give the impression, or at least cause uncertainty in the minds of my viewers that Melbourne at one time was full of double-decker trams. Is it so impossible?

An Other tram

I remember if no one else does the strange sight of the little yellow maintenance trams whizzing by late at night or early in the morning. What did they do exactly? Vacuumed up the sand from the trams' brake systems? Polished the rails? Who knows; they were cute.

A Tram