A delightful study of a tram and passengers but what are the passengers? There appears to be two nurses posing with the occupants and most of the passengers seem to wearing military/civilian gear complete with medals, caps and badges.
Well the tram says Pleasure rides on the sign and there are nurses, the advertising hoardings reflected in the glass are English so I'm assuming it's in the UK. The men on the top deck may be wearing the same uniform jacket and trousers but have a variety of military hats, so I'm assuming they're patients at a military hospital. However they aren't wearing British hospital blues and one of them seems to be flying a makeshift Belgian flag.
So my guess is an assortment of WW1 wounded Belgian soldiers who've been evacuated to Britain for treatment and are out on a joyride before repatriation.