Complex sentence: In 1912 Horsford wrote a medical paper entitled "Why voices fail" following which he attracted many singers to his practice on Harley Street and became laryngologist to the Royal College of Music, the Royal Choral Society and the Royal Society of Musicians.
Split into simpler sentences: In 1912 Horsford wrote a medical paper entitled "Why voices fail" following which he attracted many singers to his practice on Harley Street. Such was his success that he became laryngologist to the Royal College of Music, the Royal Choral Society and the Royal Society of Musicians.