Encyclopaedia Britannica, 11th Edition, "Armour Plates" to "Arundel, Earls of"

"all artillery equipped with mobile guns of 4-in. calibre and upwards," is usually composed, in Great Britain, of 5-in. or 4.7-in. Q.F. guns on field carriages. 6-in. Q.F. guns have also been used. A battery (4 guns) is attached to the divisional artillery of each division, a company of the Royal Garrison Artillery furnishing the _personnel_. The four guns are divided into two sections, each section under an officer and each subsection under a non-commissioned officer, as in the horse and field batteries. _Siege_ and _garrison artillery_ have not usually the complete and permanent organization that distinguishes field artillery. For siege trains the _materiel_ is usually kept in store, and the _personnel_ and transport are supplied from other sources according to requirement. In garrison artillery, the guns mounted in fortresses and batteries, or stored in arsenals for the purpose, furnish the _materiel_, and the companies of garrison artillery the _personnel_. In Great Britain, the Royal Garrison Artillery finds the mountain batteries and the heavy field artillery in addition to its own units. The siege trains are, as has been said, organized _ad hoc_ on each particular occasion (see FORTIFICATION AND SIEGECRAFT). In Great Britain, the guns and howitzers manned by the R.G.A. would be 6-in. and 8-in. howitzers, 4.7-in. and 6-in. guns, and still heavier howitzers, as well as the field and heavy batteries belonging to the divisions making the siege.