perhaps defective and his results, at all events as regards man, uncertain, but in animals the force and rapidity of the heart were markedly increased.  Subsequent investigations have shown very clearly the influence of music on the circulatory and respiratory systems in man as well as in animals.  That music has an apparently direct influence on the circulation of the brain is shown by the observations of Patrizi on a youth who had received a severe wound of the head which had removed a large portion of the skull wall.  The stimulus of melody produced an immediate increase in the afflux of blood to the brain.[102]

In Germany the question was investigated at about the same time by Mentz.[103] Observing the pulse with a sphygmograph and Marey tambour he found distinct evidence of an effect on the heart; when attention was given to the music the pulse was quickened, in the absence of attention it was slowed; Mentz also found that pleasurable sensations tended to slow the pulse and disagreeable ones to quicken it.

Binet and Courtier made an elaborate series of experiments on the action of music on the respiration (with the double pneumograph), the heart, and the capillary circulation (with the plethysmograph of Hallion and Comte) on a single subject, a man very sensitive to music and himself a cultured musician.  Simple musical sounds with no emotional content accelerated the respiration without changing its regularity or amplitude.  Musical fragments, mostly sung, usually well known to the subject, and having an emotional effect on him, produced respiratory irregularity either in amplitude or rapidity of breathing, in two-thirds of the trials.  Exciting music, such as military marches, accelerated the breathing more than sad melodies, but the intensity of the excitation had an effect at least as great as its quality, for intense excitations always produced both quickened and deeper breathing.  The heart was quickened in harmony with the quickened breathing.  Neither breathing nor heart was ever slowed.  As regards the capillary pulsation, an influence was exerted chiefly, if not exclusively, by gay and exciting melodies, which produced a shrinking.  Throughout the experiments it was found that the most profound physiological effects were exerted by those pieces which the subject found to be most emotional in their influence on him.[104]

Guibaud studied the question on a number of subjects, confirming and extending the conclusions of Binet and Courtier.  He found that the reactions of different individuals varied, but that for the same individual reactions were constant.  Circulatory reaction was more often manifest than respiratory reaction.  The latter might be either a simultaneous modification of depth and of rapidity or of either of these.  The circulatory reaction was a peripheral vasoconstriction with diminished fullness of pulse and slight acceleration of cardiac rhythm; there was never any distinct slowing of heart under the influence of music.  Guibaud remarks that when people say they feel a shudder at some passage of music, this sensation of cold finds its explanation in the production of a peripheral vasoconstriction which may be registered by the plethysmograph.[105]