Ney achieved virtually universal critical acclaim as a performer, with special praise for his smooth, broad viola sound.
His biography was a mystery until the musicologist Jeffrey Cooper discovered an 1877 obituary of the successful Parisian violist Louis-Casimir Escoffier, who had died aged 75.
An obituary from the 11 February 1877 edition of Revue et Gazette Musicale de Paris, "Nouvelles diverses," p. 47, reveals the identity of Casimir Ney.
Casimir Ney is most famous for his book of 24 preludes for solo viola, which are extremely difficult to play.
He also wrote a trio, a quartet and a string quintet, as well as Eighteen Caprices for Violin on the G-string, and a few works for viola and piano.