I have tested in detail, for example, the conditions of the rise of so-called "internal tunes"--we speak of "tunes in our head" or "in our ears"--and find certain suggestive influences which in most cases cause these tunes to rise and take their course. Often, when a tune springs up "in my head," the same tune has been lately sung or whistled in my hearing, though quite unnoticed at the time. Often the tunes are those heard in church the previous day or earlier. Such a tune I am entirely unable to recall voluntarily; yet when it comes into the mind's ear, so to speak, I readily recognise it as belonging to an earlier day's experience. Other cases show various accidental suggestions, such as the tune Mozart suggested by the composer's name, the tune Gentle Annie suggested by the name Annie, etc. In all these cases it is only after the tune has taken possession of consciousness and after much seeking that the suggesting influence is discovered. Closer analysis reveals certain additional facts: The "time" of such internal tunes is usually dictated by some rhythmical subconscious occurrence. 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. For example, I once found a tune "in my head" which was perfectly familiar, but for which I could find no words. Tested on the piano, the pitch was F-sharp and the time was my heart beat. Finally, after much effort, I got the unworthy words "Wait till the clouds roll by" by humming the tune over repeatedly. The pitch is determined probably by the accidental condition of the auditory centre in the brain or by the pitch of the external sound which serves as stimulus to the tune.