BODY AND MIND. 211 



deepest thought with " eyes in the mind," although ostensibly bent 

 on outward things and when we find our steps guided harmoniously 

 towards our appointed end, illustrates but another phase of the 

 unconscious ruling of our lives. And the phenomena of the sleep- 

 vigil, when, wrapt in the mantle of fancies and acted thoughts, we 

 may walk fearlessly on the house-tops, show us in another fashion the 

 action of active brain and body upon unconscious mind. 



Thus it seems perfectly clear that in many of our daily actions 

 we pass automatically through existence, dreaming no more than 

 does the wound-up watch of the mechanism in virtue of which we 

 execute our common movements, but regulated at the same time by 

 an internal power which now and then asserts its sway over the vital 

 machinery, as if to remind us that we possess the higher attributes of 

 reason and will. If it be true, as we have shown, that over the 

 bodily processes brain asserts an autocratic sway, it is equally note- 

 worthy that under the influence of what, for want of a clearer term, 

 we may call conscious mind, the automatic rigour and regularity of 

 life may be suspended and overruled. Take as a fitting and as an 

 interesting example the difference between the ordinary unconstrained 

 action of the heart and its behaviour under the influence of mental 

 emotion. If, as Cowper figuratively puts it, 



The heart 

 May give a useful lesson to the head, 



it is no less true physiologically that the head may occasionally give 

 anything but a salutary lesson to the heart. It was Moliere and 

 Swift who, in their day, justly ridiculed, as physiology proves, the idea 

 that the heart's regular action depended upon some mysterious 

 "pulsific virtue." Within the hearts own substance and it must 

 be borne in mind the centre of the circulation is simply a hollow 

 muscle lie minute " sympathetic " nerves and nerve masses which 

 govern its ordinary movements, and are responsible for its uncon- 

 strained working. The regular motions of the heart thus present 

 little difficulty in the way of theoretically understanding their origin 

 and continuance. As other muscles such as those of the eyelids or 

 of the breathing apparatus possess a regular action, and are stimu- 

 lated at more or less definite intervals, so the heart itself simply acts 

 in obedience to the defined nervous stimulation it undergoes. But 

 it so happens, that other two sets of nerves are concerned more or 

 less intimately in the affairs of the heart. From the sympathetic 

 system, an important nerve trunk enters into the heart's substance. 

 This trunk is independent in nature of the sympathetic nerve masses 

 which control the ordinary movements of the heart. But the sys- 

 tem of nerves which owns the brain as its head, also possesses a 

 share in the heart's regulation. Nerves are supplied to the organ 

 from a very remarkable branch, which, with more respect for scien- 



p 2 



