Very often it is the case that new corns, both hard and soft, grow up in the places where they have been taken away before, re-appearing, some of them, several times; and it is a question if the common practice of putting leather with a hole in it around the corn does not tend to make the latter grow up again by pressing on the edges of the cavity. It is perhaps better, therefore, that the leather or felt be worn for some time after the corn is gone, to keep the pressure of the boot away from the part till it has regained its natural condition, and it is well to make the hole in the plaster _so large_, that even the border of the sensitive cavity will not be touched. When a surface has been secreting corn-material for a length of time, it is not strange that it should continue the habit without much provocation. In these cases where the corn grows again, it may perhaps be advisable to touch the most central part, or place of the _point_, with nitric acid or some other caustic, to destroy the papillæ, and change the structure of the skin, as is done with a wart; where it is so effectual that the wart never re-appears. It is not necessary to burn the surrounding surface, or make anything more than a very small burn anywhere. The acid should be applied with some sharp-pointed instrument, just wet with it, so there shall be no danger of putting on too much. If there is any fear of creating too much inflammation, it can be postponed till the acute sensitiveness has become somewhat abated. For soft corns it is doubtful whether any other treatment than burning will be completely successful, though it may be well to try some other method first. Burning is rather severe, but reasonably sure, and a thousand times better, than to suffer from the corn. But little acid need be applied at a time, and as soon as the under skin becomes inflamed the desired effect is accomplished; for when it heals, the corn is “done for” and gone. Something soft may be put between the toes to separate them, and prevent any unnecessary irritation during the process. Corns on the bottom of the foot are amenable to caustic like the rest, the felt sole with a hole in it being used for protection during the operation. Inflamed and suppurated corns are to be cut down as much as possible and lanced, according to Erichsen—one of the best authorities—though it would seem to one unacquainted with the matter that they might be removed like the others. They are intensely painful, and a surgeon’s skill is necessary to treat them properly. Some of the medical books represent that there is more or less danger in using caustics in severe cases, where the patient is an old person, or one of feeble vitality, or extreme nervous sensibility. It is always well to proceed safely, and have medical advice before operating on such a patient.