Congelation has been used in two forms-first in the form of liquid air,* which was always difficult to obtain and more difficult to keep, and in the form of carbon dioxide snow, as advocated by Pusey.20 The snow is best obtained by loosely screwing a small brass cylinder to the outlet valve of a commercial tube of the gas, which is supplied to all druggists for the purpose of charging their soda water, and then tightly tying a piece of chamois over the end of the tube. In this way a molded pencil of the snow is obtained ready for use. It is best handled in a pair of heavy, lined automobile gloves, and is applied to the growth for from one to three minutes, making firm pressure. The action is essentially caustic, and is not very deep. The author has seen it used in only four instances of cancer, and in all of them there was prompt recurrence; hence he does not advocate this form, of treatment. Some other dermatologists, however, report successes from its use.