[2] In 1871 he studied for a year at Royal College of Science for Ireland to improve his theoretical knowledge before gaining a Whitworth scholarship in 1872[4] and attending Queen's University Belfast.

[13] Henry Cowie, some 20 years younger than Robert Coey, joined the BNCR in 1885 and rose to chief clerk in the general manager's office of the NCC before retiring in 1931.

[18] The final 12 of these engines, the Class 321/D2, were noted for their work on Cork and Limerick expresses and occasionally standing-in for 4-6-0 absences, being described by Boocock as follows "their life of more than 50 years was well earned, being a true R. Coey product, simple and reliable".

[21] Coey also receives part credit for the one-off 1912 4-4-0 Sir William Goulding that was to be used on the flagship Limited Mail Express services between Dublin and Cork.

[15] The steam railmotor came into use for lightly used branch services in the first decade of the 1900s, and several rail operating companies in Ireland imported examples though they were generally not successful.

Tried on Kingsbridge—Amiens Street services, then Cashel and Killaloe branches it proved to use coal very inefficiently and was unable to haul a trailer car.