[1] Canon de 100 mm Modèle 1891 guns armed a variety of ships such as armored cruisers, coastal defense ships, destroyers, gunboats, minesweepers, pre-dreadnought battleships, protected cruisers and seaplane tenders of the French, Bulgarian, Haitian, Polish, Portuguese, Romanian and Turkish navies.

[3] Poland had two Modèle 1891 guns in service as coastal artillery under the designation Canet 100 mm wz.

However it was found that the guns were too heavy for the ships and two Russian made Canet 75mm 50 caliber Pattern 1892 were fitted instead.

[5] In 1932 the two guns formed the 13th coastal artillery battery was created at Oksywie to defend the approaches to the Port of Gdynia.

The theorists hadn't foreseen that trenches, barbed wire, and machine guns had robbed them of the mobility they had been counting on and the combatants scrambled to find anything that could provide long range counter battery fire.

Like many of its contemporaries, it had a tall and narrow box trail carriage built from bolted iron plates with two wooden spoked wheels.

The carriages were tall because the guns were designed to sit behind a parapet with the barrel overhanging the front.

The wheels could be fitted with detachable grousers designed by the Italian major Crispino Bonagente for traction on soft ground and these consisted of rectangular plates connected with elastic links and are visible in many photographs of World War I artillery from all of the combatants.