Your recent note in "Miscellany" regarding the magnificent service rendered by pigeons during the war (writes a correspondent) reminded me of a telegram once received at a certain R.A.F. headquarters where I was serving. It announced the arrival in Egypt of "300 pigeons and 3 Other Ranks."
At least they warranted initial capital letters, as is still the case in the British Army. The earliest documentation of the term in the OED is from 1904 Regulations for Mobilization (with a z), in which it does not have capitals.