Shakespeare Memorial Fountain - Leicester Square, London, UK - Fountains on Waymarking.com

The plinth of the statue sits within the fountains cistern. From the cistern the water is pumped to four dolphins at the base of the plinth where it is ejected from the tops of the heads of the dolphins back into the cistern.

The Speel Blog tells us about the square, statue and fountain:

Leicester Square is of enough importance to London that it is worth noting the statues there, even though they are not worth going to see for themselves. By way of excuse, part of Leicester Square's charm arises from its unpretentious, intimate feel, and large monuments would probably be inappropriate.

The only 'monument' as such in the square is the central marble fountain, with Shakespeare on top, and dolphin accoutrements around. The sculptor was G. Fontana, working in the 1870s, and he copied the statue from one in Westminster Abbey, designed by the architect William Kent, and sculpted by the eminent sculptor Peter Scheemakers. Leicester Square was purchased for the nation by Baron Grant in 1874. Baron Grant's title, apparently, was an Italian one, given to him by the City of Milan for financing the Galleria Vittorio Emanuele in that city. Baron Grant's fortune was large - he spent £30,000 buying the square and fitting it out. As well as the central Shakespeare statue, four busts in white marble on granite pedestals, all of a similar date, were placed at the corner sites. All four are in bad shape - Newton by William Calder Marshall is the most decayed. The others are a rather feeble Sir Joshua Reynolds (the first President of the Royal Academy) by Henry Weekes, John Hunter (a pioneer of surgery) by Woolner, and a rather spirited bust of Hogarth by Joseph Durham. They were removed in the 2011/12 revamp of the square, and have not yet been returned.

The statue and fountain are Grade II listed with the entry at the English Heritage website telling us:

Memorial sculptural fountain in centre of garden with busts to four corners. 1874 garden design by James Knowles with fountain sculpture by G. Fontana. White marble. "Stratford" statue of the Bard on tall square pedestal with dolphin supporters at angles over stepped circular plinth rising from inner basin, outer basin as flower bed compartmented by volute scrolls, the outer rim with pedestalled vases. The marble busts on granite plinths part of the same 1874 layout: Hogarth by J. Denham, John Hunter by T. Woolner, Isaac Newton by Calder Marshall, Reynolds by H. Weekes.