In surgical office work, there is occasionally the need of a rapid and fleeting anesthesia which does not necessitate the use of a cumbersome apparatus for its induction. In these cases, in place of chloroform, anaesthol or ether, the ethyl chloride spray can be used on the Schimmelbusch mask already described. It produces a prompt anesthesia during which an abscess can be opened, washed and dressed without causing the patient the slightest pain.