Joachim

Doctor Joachim held a concert with Leonard Borwick on the evening of Friday 1 July 1898 at St James' Hall, where the pair played sonatas for the piano and violin. An advert for the concert appeared in a copy of The Times. (TV: Deep Breath)

Behind the scenes
The "Dr Joachim" mentioned in The Times is most likely Joseph Joachim; a 19th century violinist and associate of the pianist Leonard Borwick. In the real world, Joachim received an honorary Doctorate of Music from Cambridge University.