In some establishments, the upper half of a stall, or one corner of a loose box, is laid with wet clay. A horse having tender, contracted, or brittle fore-feet, is put into this for one or two hours every day. Sometimes the floor of a loose box is entirely covered with the wet clay, and the horse turned into it all day, being stabled at night, that he may lie dry. The clay-box is good for some feet, and bad for others. It is used with too little discrimination for all defects of the feet, real or supposed. When the clay is very wet, the moisture softens the horn, increases its growth, expands the hoof, and brings down the sole. It also cools the foot, and tends to subdue inflammation. When the horse is of little weight, his feet strong, contracted, rather hot, and the heels high, the clay may be thoroughly soaked with water; the horse's shoes had better be off, and he may stand in the clay all day for eight or ten successive days, if not at work. If working, one or two hours every second day will be sufficient. When the crust and sole are rather thin and weak, the latter tending downward, the growth of horn deficient, the clay should be tougher, having no loose water about it, the horse's shoes should be kept on, and he may stand in the clay two hours every day.

In the first case the sole is to be lowered, the foot expanded and cooled; in the second, the growth of horn is to be stimulated, and the sole supported. The horn would grow faster if there were more moisture; but were the clay softer it would not afford sufficient support Additional moisture may be given to the crust by means of a swab. The clay-box is not good for thrushy feet, but in trifling cases the frog may be protected by a pitch or other waterproof covering.