C. C. Massey

According to Readers Guide to The Mahatma Letters to A. P. Sinnett:

Massey, Charles Carlton, an English lawyer much interested in spiritualism. He went to the USA in 1875 to visit Chittenden, Vermont, to verify for himself HSO's accounts of the Eddy phenomena (See ODL 1) and became a life-long friend of HSO. He was one of the first members of the TS and later a founder and first president of the TS in England. He was also one of the founders of the Psychical Research Society and, after the Hodgson Report was issued, he resigned from the TS. HPB tried hard to get the Mahatmas to teach him but they refused (ML, pp. 411-12). See SH, p. 112, for a brief resume of his career. ML index.

Master K.H. regarded him as a very honest person, but considered he was not strong enough to become a chela. In one of his letters he wrote:

Doubtless a more sincere, truthful or a more noble minded man (S. Moses not excepted) could hardly be found among the British theosophists. His only and chief fault is — weakness. Were he to learn some day how deeply he has wronged H.P.B. in thought — no man would feel more miserable over it than himself.