Permission for a swim in the Westminster Road Baths in Kirkdale was granted by the Baths and Wash Houses Department of the Liverpool Corporation. The Baths Manager, Mr John Davenport, supervised the event. Admission was one shilling from the start of the swim on Friday, but from 5.00 p.m. onwards on Saturday the charge increased to two shillings and sixpence.

Mercedes entered the 100-ft long pool at 4.00 p.m. on Friday 28 March and, swimming in rounds, completed the 31-hour swim at 11.00 p.m. on Saturday evening.

Continuous music energised her throughout, especially during the early hours of the morning. The repertoire on this occasion included the Barcarolle from The Tales of Hoffman, Liszt’s Hungarian Rhapsody, Life’s Dream is O’er, and The Blue Danube.

Amongst the timekeepers were members of staff from the Liverpool branches of Owen Owen Limited (Mr Harding, Mr Ayres, Mr Thomas and Mr Oversby), and from Lewis’s Limited and Bon Marché Limited (Miss Dodwell and Miss Mackle).

At the finish she had to be lifted out of the water and taken to the Montgomery Antrim Hotel on a stretcher to recover her land legs. A police surgeon who examined her before and after the swim confirmed that her pulse was normal and the swim had resulted in no strain at all on her heart. 

Dr Cantillon, a medical practitioner who had attended her on a previous endurance swim, accompanied her back to the hotel and reported that her condition after such a physical test was excellent. Mercedes put this lack of stress down to the fact that her method of swimming was so effortless.

It was reported in the Liverpool Daily Post that hundreds of people inside the baths and many hundreds more waiting in the streets outside the building, cheered when she was carried out to a waiting ambulance.

Miss Hilda James (the 1920 Olympic Silver Medallist and British record holder for every speed swim from 150 yards to one mile) arrived unannounced at the event, and volunteered to feed and observe Mercedes throughout Friday night. Mercedes did not realise at first that she was being attended by the famous Liverpool swimmer until someone eventually introduced them.

It was apparent that Hilda’s interest in the art of swimming was not just confined to speed, and her support of the event was very much appreciated by Mercedes.