On the Cavalry Commander (4.3-4.4)

Just as the food and exercise of the horse must be attended to in order that he may keep sound, so his feet must be cared for. Now damp and slippery floors ruin even well-formed hoofs. In order that they may not be damp, the floors should have a slope to carry off the wet, and, that they may not be slippery, they should be paved all over with stones, each one about the size of the hoof. Such floors, indeed, have another advantage because they harden the feet of the horses standing on them.

To take the next point: the groom must lead out the horse to clean him, and must loose him from the stall after the morning feed, that he may return to his evening feed with more appetite. Now the stableyard will be of the best form and will strengthen the feet if he throws down and spreads over it four or five loads of round stones, the size of a fist, about a pound in weight, and surrounds them with a border of iron so that they may not be scattered. Standing on these will have the same effect as if the horse walked on a stone road for some time every day.