Blue Tram Oil

A little pressie for S (who has a penchant for things blue, trains, and Sheffield's trams) to mark the final submission of his PhD thesis (on something maths-ecology-related).  A milestone his father didn't manage.

As per the implication of yesterday's blip, of the waterslide transfers, the tankers were hurriedly repainted white from their original blue - actually it works OK but I'd rather not have had to paint them twice!