IN A RECENT publication1 we described in detail a method for the quantitative evaluation of the irritation which cigaret smoke causes as judged by its edema-producing properties, based on gravimetric determination of the increase of the moisture content of the upper palpebral conjunctiva of a rabbit's eye that has been exposed to cigaret smoke. The method is briefly as follows:
A smoking machine of the type described by Bradford, Harlan and Hanmer,2 which draws a 35 cc. puff once a minute, is used. Three puffs, as a rule, are directed through a suitable cup placed over the widely opened eye of the morphinized rabbit. When one eye only of each rabbit is exposed, the other serving as a control, we name the technic procedure A. When both eyes of each rabbit are exposed, thereby permitting comparison of two cigarets on the same animal, the technic is called procedure B. In