by the pneumograph I read that the breathing is easier or quicker, depending on whether the emotions are pleasant or unpleasant. I have performed this year more than two thousand of those experiments."
"Good! I have a problem in which you can be of the very greatest use to me; and the plethysmograph and the pneumograph will serve my purpose as well as any other instrument in the laboratory. For no matter how hardened a man may be, no matter how impossible it may have become to detect his feelings in his face or bearing, he cannot prevent the volume of blood in his hand from decreasing, and his breathing from becoming different, under the influence of emotions of fear or guilt. By the way, professor, is Mr. Welter familiar with these experiments of yours?"
"What, he!" cried the stout German. "For why should I tell him about them? He knows nothing. He has bought my time to instruct classes; he has not bought, py chiminey! everything—even the soul Gott gave me!"
"But he would be interested in them?"
"To be sure, he would be interested in them! He would bring in his automobile three or four other fat money-makers, and he would show me off before them. He would make his trained bear—that is me—dance!"
"Good!" cried Trant again, excitedly. "Professor Schmalz, would you be willing to give a little exhibition of the plethysmograph and pneumograph, this evening, if possible, and arrange for President Welter to attend it?"
The astute German cast on him a quick glance of in-
