What is "artillery wheel"

Artillery wheel \Ar*til"ler*y wheel\ A kind of heavily built dished wheel with a long axle box, used on gun carriages, usually having 14 spokes and 7 felloes; hence, a wheel of similar construction for use on automobiles, etc.

The artillery wheel was developed for use on gun carriages when it was found that the lateral forces involved in horse artillery manoeuvres caused normally constructed cart wheels to collapse. Rather than having its spokes mortised into a wooden nave (hub), it has them fitted together ( mitred) then bolted into a metal nave. Its tyre is shrunk onto the rim in the usual way but it is also bolted on for security. A normal wagon wheel is dished so that in its lowest part, the spokes are perpendicular to the ground thus supporting the weight (with the axle not truly horizontal but angled downward toward the outside about 5 degrees). This is not done with artillery wheels.