Page:Popular Science Monthly Volume 49.djvu/870

846 were presented in an illustrated lecture by Prof. Cope and Mr. H. C. Mercer; and the making of the Mammoth Cave was explained, and a colossal cave discovered a year ago in Kentucky was described by Prof. Hovey. The last gentleman urged the formation of an American cave club. The section resolved to place a tablet on the spot where the Association of American Geologists was founded. In the Section of Mechanical Science Mr. W. S. Aldrich advocated a national endowment for engineering research, and the subject of irrigation for the eastern United States was brought to attention. The practical side of chemistry was presented in such subjects as The Chemical Problems of the Pottery Industry, Sugar-making at the Present Day, and The Use of Coal-Tar Products in Food.

In choosing Prof. Wolcott Gibbs as the president of its next meeting, the association has honored itself in honoring a veteran chemist who was famous when the majority of its present most active members were still schoolboys.



have here a popular view of one division of the fruitful field that is being worked by the physiological psychologists of the present generation in Italy. The author lays a broad foundation for his treatment of his subject by describing the general functions of each part of the brain and those of the spinal cord. He then takes up the circulation of the blood in the brain during emotion, on which he has made extended researches. He has had opportunities to take tracings from the pulsations of the brain in patients whose skulls had been fractured, and shows that any sound or sight that stimulates mental action increases the quantity of blood sent to the brain. He has tested the same thing also with a balance devised by him which has a beam large enough for a person to lie at length upon. Any mental excitement of the subject on the balance inducing a rush of blood to the brain would cause the head end of the delicately poised beam to sink. When the normal condition of the subject was restored the balance would regain its equilibrium. Dr. Mosso has also taken many tracings from the respiration, the beating of the heart, and the circulation of blood in the hands, each class of records showing the perturbations produced by excitement. The variation in the quantity of blood sent to the hands and other outlying parts of the body underlies the phenomenon of pallor, which with oppression of the chest and quickened beating of the heart are among symptoms of fear. Trembling is another one of these symptoms which Dr. Mosso examines. Taking up facial expression, he describes the nervous and muscular actions by which expression is produced, and follows this with a chapter on the physiognomy of pain, in which he gives a series of photographs of a hospital patient undergoing a