“Professor Schmalz,” said Trant, following him into the laboratory, and glancing from one to another of the delicate instruments with keen interest, “tell me along what line you are now working.”
“Ach! I have been for a year now experimenting with the plethysmograph and the pneumograph. I make a taste, I make a smell, or I make a noise to excite feeling in the subject; and I read by the plethysmograph that the volume of blood in the hand decreases under the emotions and that the pulse quickens; and 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 instruments 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 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 interrogation. “Why not?” he said. “It makes nothing to me what purpose you will be carrying out; no, py chiminey! not if it costs me my position of trained bear; because I have confidence in my psychology that it will not make any innocent man suffer!”
“And you will have two or three scientists present to watch the experiments? And you will allow me to be there also and assist?”
“With great pleasure.”