To determine the effect of the resin content of tobacco in cigarettes upon the amt. of nicotine absorbed by human subjects during smoking, 4 kinds of cigarettes were prepared from; 1. A resin rich tobacco (9.98% resin and waxes); 2. Resin poor, same tobacco extracted with ether (5.44% resins and waxes); 3. A mixture of resin rich tobaccos (10.61% resins and waxes); 4. A mixture of resin poor tobaccos (7.35% resins and waxes). A commercial brand of cigarettes was also tested. The subject was a moderate smoker, 42 yrs. old, who smoked with inhaling and without inhaling. In both cases, the air from the mouth was collected in a tube leading to an absorption apparatus consisting of a series of 5 absorption flasks connected to an H2O pump. The first flask contained 50 ml. N/10 H2SO4 and the others, 35 ml. Nicotine was detd. by the method of Pfyl and Schmitt (Z. Unters. Leb. mitt. 54: 60.1927). The 2d flask contained most of the nicotine, the 1st, 3d, and 4th, small amts. and the 5th, none. Nicotine was also detd. in the saliva and mouth washings. Twenty cigarettes were smoked for each test. The amt. of nicotine absorbed by the body was obtained by adding together the amt. of nicotine in the absorption apparatus, and that in the saliva and mouth washings of the inhaled smoke, and subtracting this sum from the amt. of nicotine in the smoke that was not inhaled. The amt. of resin in the tobacco had no influence upon the amt. of nicotine absorbed by the subject. Considerable nicotine was absorbed in the air passages leading to the lungs as well as in the lungs. When the cigarettes were smoked without inhalation, 5%, with weak or moderate inhalation, 66-76%, and with strong inhalation, 84-95% of the nicotine in the smoke reaching the mouth was absorbed by the subject.