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So, too, in throwing out the arms in the act of falling, a kind of intuitive judgment is exercised as to which direction the movements of the arms shall take. In my own opinion, both of these instances are more properly to be assigned to what Hartley called secondarily automatic movements. That is, "actions which come to be performed by habit, without will or even consciousness, though originally learned and practised with conscious interest." For in the lowest forms of idiocy these precautionary or protective movements do not occur.

For the well-performance of these reflex movements, it is necessary that the ingoing nerve should be in a condition properly to convey the influence from without, that the ganglionic centres are ready to convert this into an appropriate impulse, and the efferent nerve fit to transmit this impulse to fulfil its purpose. In other words, the machine must be in order.

Dr. Fox has expressed the opinion, "that of congenital cases of idiocy (especially those of low type), while the physical cause is often spoken of as an arrest of development, the abnormal incompleteness is more commonly dependent either on injury to the foetus, or on some disease occurring during foetal life. The brain, then, being formed late in the order of development is more likely to suffer from any injury to or diseases of the foetus than other portions of the nervous system." This may be true of extreme cases of incompleteness in the nervous masses, the monstrosities recorded from time to time; yet, judging by my own experience, I cannot but regard the majority of cases submitted to my care as less the result of disease or injury than of ill-nourishment of the foetus. Sometimes it is due to general weakness in the reproductive organs of either parent -- sometimes due to the fact that the maternal energy is wasted in other directions; as, for example, exhaustive physical or mental labor, anxiety, or even conformity to the unnatural requirements of modern social life.

In idiots, then, of low degree we might predicate imperfection and infirmity of the general nervous system in conductive and ganglionic power. At all events, in some extreme cases of idiocy there is this defect. Let me give a few illustrations. Dr. Howe, in his report for 1850, described the case of an adult idiot, who sometimes in cramming food into his mouth caught his fingers between his teeth, and, not knowing what pained him, used to howl and bite harder and harder until he was severely hurt. It is not an infrequent circumstance to see idiots of low grade when angry, beat themselves. You have all doubtless seen cases where flies settling on the face would excite no movement of the facial muscles, no apparent sense of uneasiness. In one of my early reports I described a case where the function of deglutition was ill-performed. The eyeball could be touched without exciting the act of winking. The same girl had never walked or even sat up without support on all sides. She could not maintain her equilibrium under any circumstances, and when unsupported would always fall obedient to the law of gravitation, without moving a muscle to save herself from injury. I have in other cases tried explosions of various sorts, where neither the flash nor the noise would produce winking. The reflex movement in this case being dependent upon sight and hearing, and these special senses being inactive, the necessary stimulus to the reflex movement was wanting.

In some of the cases that have fallen under my observation the responsive movement is not distinctly purposive, but rather a vague convulsive motion of all the limbs when one is irritated. It has seemed to me that, as a rule, the lower extremities have responded more promptly to irritation than the upper.

In pulmonary affections, in our lowest class of cases, the cough is often wanting; in other words, the irritation of the mucous membrane which should produce a cough, as a reflex, fails to do so,

These are the simpler forms of reflex action requiring no very complicated nervous apparatus. I have mentioned that in extreme cases of idiocy this apparatus may be defective and the function ill-performed. Yet these movements are so essential to the sustenance of life, that idiots who have vitality enough to reach an institution-attending age will generally manifest these reflex movements, though perhaps with less than normal promptness.

On the other hand, with a certain class of cases the reflex movements are excessive, -- that is, in the absence of the inhibitory influence of the intelligence and will the manifestations are more marked.

But there is a broader range of reflex action. Besides the simple illustrations already given, the human organism is made up of a multitude of mechanisms acting automatically to perform certain work. Some of these are very complicated, as is seen by late physiological experiments.

Some of these are strictly reflex, -- set in motion by the application of stimuli, and then the successive processes of the mechanisms are executed. Even these are not without a degree of adaptation, as has been witnessed in the lower forms of animal life.