Allan

It was attached to the Quartermaster Generals’s Department and not to the Ordnance Corps.

In addition to Rory’s suggestions:

The Royal Staff Corps

The Regimental Companion: Containing the Pay, Allowances and Relative Duties of Every Officer in the British Service, Volume 3

Pages 338-341

https://books.google.ca/books?id=Ybk_AAAAYAAJ&pg=PA338&dq=

Standing Orders of the Royal Staff Corps

https://books.google.ca/books?id=fEQIAAAAQAAJ&printsec=frontcover&dq=

Good hunting

Ron