We found Kennedy arranging an instrument in the music-room which adjoined the library.  From what little knowledge I have of electricity I should have said it was, in part at least, a galvanometer, one of those instruments which register the intensity of minute electric currents.  As nearly as I could make out, in this case the galvanometer was so arranged that its action swung to one side or the other a little concave mirror hung from a framework which rested on the table.  Directly in front of it was an electric light, and the reflection of the light was caught in the mirror and focused by its concavity upon a point to one side of the light.  Back of it was a long strip of ground glass and an arrow point, attached to which was a pen which touched a roll of paper.

On the large table in the library itself Kennedy had placed in the centre a transverse board partition, high enough so that two people seated could see each other’s faces and converse over it, but could not see each other’s hands.  On one side of the partition were two metal domes which were fixed to a board set on the table.  On the other side, in addition to space on which he could write, Kennedy had arranged what looked like one of these new miniature moving-picture apparatuses operated by electricity.  Indeed, I felt that it must be that, for directly in front of it, hanging on the wall, in plain view of any one seated on the side of the table containing the metal domes, was a large white sheet.

The time for the experiment, whatever its nature might be, had at last arrived, and Dr. Guthrie introduced Mr. and Mrs. Willoughby to us as specialists whom he had persuaded with great difficulty to come down from New York.  Mr. Willoughby he requested to remain outside until after the tests.  She seemed perfectly calm as she greeted us, and looked with curiosity at the paraphernalia which Kennedy had installed in her library.  Kennedy, who was putting some finishing touches on it, was talking in a low voice to reassure her.

“If you will sit here, please, Mrs. Willoughby, and place your hands on these two brass domes—­there, that’s it.  This is just a little arrangement to test your nervous condition.  Dr. Guthrie, who understands it, will take his position outside in the music-room at that other table.  Walter, just switch off that light, please.

“Mrs. Willoughby, I may say that in testing, say, the memory, we psychologists have recently developed two tests, the event test, where something is made to happen before a person’s eyes and later he is asked to describe it, and the picture test, where a picture is shown for a certain length of time, after which the patient is also asked to describe what was in the picture.  I have endeavoured to combine these two ideas by using the moving-picture machine which you see here.  I am going to show three reels of films.”