The Great Ruby opened at Drury Lane in the autumn of 1898. The sets were by William Perkins, R Caney, and Bruce Smith and it was 'Sensation' Smith who was responsible for the sequence you see here.
A review in Punch gives an excellent description of events: 'Mrs Henry Wood, the heroine, was in a balloon over Hampstead Heath with the villain hanging on by his eyelids to the car ... Mrs Wood loosened his hold and chucked him over ... the Balloon business is not precisely a novelty but never was the situation more realistically represented. Drury Lane vibrated with enthusiasm'.
Smith carefully placed the circus tent at stage left (the right as we look) so that as the balloon ascended, the tent was lowered to exaggerate the effect. Cloud then obscured the balloon temporarily so that a smaller version could replace it, giving the effect of being higher up and further off.