"Alumni Cantabrigienses (the standard list of Cambridge alumni) has the following entry for your grandfather:
HUMPHREYS, ROBERT.
Admitted pensioner (i.e. an undergraduate who paid for his own fees) at TRINITY, Oct. 10. 1893.
Son of Robert, of Hayfield, Cork.
Born July 2, 1871, at Cork.
School, Cork (Mr Fawcett).
Matriculated Michaelmas 1893.
BA (University of Ireland & Trinity College Cambridge);
Humphreys' name appears in the printed list of Resident Members of the University dated 14 Oct. 1893, when he was living at 21 Malcolm Street, and in the next edition, dated 25 April 1894, when he had the privilege of rooms on R staircase in 'Old Court' (now known as Great Court). But his name does not occur in the next list, dated 13 Oct. 1894, by which date, it would appear from what you say, he was serving in India. It would therefore appear that he left Trinity before completing a full year here, and certainly he did not obtain a degree from this University. I am unable to say what the connection with the University of Ireland may be. I presume, however (if the statement is correct), that he somehow obtained a degree from that University at a later date, and that the reference to this College in the I.C.S. List simply indicates that he resided here for a while. "