There are, of course, many surface manifestations of excitement. The contraction of blood vessels with resulting pallor, the pouring out of “cold sweat,” the stopping of saliva-flow so that the “tongue cleaves to the roof of the mouth,” the dilation of the pupils, the rising of the hairs, the rapid beating of the heart, the hurried respiration, the trembling and twitching of the muscles, especially those about the lips--all these bodily changes are well recognized accompaniments of pain and great emotional disturbance, such as fear, horror and deep disgust. But these disturbances of the even routine of life, which have been commonly noted, are mainly superficial and therefore readily observable. Even the increased rapidity of the heart beat is noted at the surface in the pulsing of the arteries. There are, however, other organs, hidden deep in the body, which do not reveal so obviously as the structures near or in the skin, the disturbances of action which attend states of intense feeling. Special methods must be used to determine whether these deep-lying organs also are included in the complex of an emotional[*] agitation. *[Footnote: In the use of the term “emotion” the meaning here is not restricted to violent affective states, but includes “feelings” and other affective experiences. At times, also, in order to avoid awkward expressions, the term is used in the popular manner, as if the “feeling” caused the bodily change.] Among the organs that are affected to an important degree by feelings are those concerned with digestion. And the relations of feelings to the activities of the alimentary canal are of particular interest, because recent investigations have shown that not only are the first stages of the digestive process normally started by the pleasurable taste and smell and sight of food, but also that pain and great emotional excitement can seriously interfere with the starting of the process or its continuation after it has been started. Thus there may be a conflict of feelings and of their bodily accompaniments--a conflict the interesting bearing of which we shall consider later. Emotions Favorable to Normal Secretion of the Digestive Juices