The effect of the smoking of tobacco on the circulation of man has been the subject of many excellent papers. Comprehensive investigations of the pharmacologic and physiologic action of tobacco smoke and nicotine have been reported elsewhere and are not within the scope of this paper.
The vasoconstrictor action of smoking tobacco was first demonstrated by Bruce and his associates1 in 1909 by means of the plethysmograph. Hesse2 in 1907 and Lee3 in 1908 had observed that smoking produced an elevation of the blood pressure and an increase of the pulse rate. Since that time it has been further recognized that the smoking of cigarets produces vasoconstriction characterized by a decrease of cutaneous temperatures of the extremities or plethysmographically by a decrease of the velocity of blood flow together with an elevation of blood pressure and pulse rate. Renewed interest in the effects of the smoking of