After hearty meals it is always the time of the heart beat, unless there be "in the air" some more impressive stimulus; as, for example, when on shipboard, the beat is with me invariably that of the engine throbs.

When walking it is the rhythm of the footfall.

On one occasion a knock of four beats on the door started the Marseillaise in my ear; following up this clew, I found that at any time different divisions of musical time being struck on the table at will by another person, tunes would spring up and run on, getting their cue from the measures suggested.

Further, when a tune dies away, its last notes often suggest, some time after, another having a similar movement--just as we pass from one tune to another in a "medley." It may also be noted that in my case the tune memories are auditive: they run in my head when I have no words for them and have never sung them--an experience which is consistent with the fact that these "internal tunes" arise in childhood before the faculty of speech.

They also have distinct pitch.