“in producing its effect on the listener, the mode is never the sole factor.” In a later study Hevner[48] continues to maintain that modality is effective in the dimensions of sadness and happiness but quite useless in the dimensions of vigor, excitement and dignity. The reaction to mode is influenced by what has been heard immediately previously, and by musical training. The reaction to mode is not physiologic but offers one key to music for patients in that those who identify the minor mode with sadness should not be given such music when gay music is indicated. _Key._ There was a time when particular keys were credited with emotional powers. Lest such thoughts still persist, the following quotation from Gurney[40] is offered. “Particular keys are sometimes credited with definite emotional powers. That certain faint differences exist between them on certain instruments is undeniable, though it is a difference which only exceptional ears detect. The relations between the notes of every key being identical, every series of relations presenting every sort of describable or indescribable character will of course be accepted by the ear in any key, or if it is a series which modulates through a set of several keys, in any set of similarly related keys. But as it must have a highest and a lowest note it will be important, especially in writing for a particular instrument, to choose such a key that these notes shall not be inconvenient or impossible; and also the mechanical difficulties of an instrument may make certain keys preferable for certain passages. Subject to corrections from considerations of this sort, the composer probably generally chooses the key in which the gem of his work first flashes across his mind’s eye: and when the music has once been seen and known, written in a certain key, the very look of it becomes so associated with itself, that the idea of changing the key may produce a certain shock. But the cases are few indeed where, had the music been first presented to any one’s ears in a key differing by a semitone from that in which it actually stands, he would have perceived the slightest necessity for alteration; and as a matter of fact when a bit of music is thought over, or hummed or whistled, unless by a person of exceptionally gifted ear it is naturally far oftener than not in some different key to that in which it has been written and heard. Even the difference most commonly alleged, between C major as bright and strong and D flat as soft and veiled, comes to almost nothing when a bright piece is played in D flat or a dreamy one in C.