The St. Johns herald., 1889-10-17

of its own apartment Gas represented
 by its shelly for time, you gre me e
 ly witnessing reflex action in lower
 life. The sensation of touch has
 been transmitted to the nervous
 centers of the snail, and those
 centers in their turn have issued
 their commands to the muscles with
 the result of producing the compulsory
 retirement just named. It is with
 this reflex action as though one out
 side official (the sense orgal) receiv-
 ing a message. transmits it to head
 quarters (the brain or nerve-center); ;
 whilo the latter, ,dealing.witht the emer-
 gency which has arisen, issues the
 commands to other officials (muscles,
 for example), and these latter carry
 out the movements necessary for the
 welfare of the state. Even when the
 mouth waters" at the sight of dain
 ties-a phase of life extremely well
 seen in dogs who view from point of
 expectancy the dining arrangements
 of their master5-it is a reflex action
 which is responsible for this piece of
 physiological foolishness. The sensa-
 tion Of sight conveyed to the brain is
 reflected to the salivary glands of
 the mouth, and these discharge into
 the mouth their special fluid, which,
 of course. is of service in digestion.
 It is simply a matter of habit which induces the flow of saliva when there Is nothing present to taste O. to di- gest, and. so far, this action, like many others of higher and lower life alike, is of unconscious or automatic kind.
 Study this curious principle of nerv- ous action a little more closely, and one recognizes that it depends upon the existence of a tole ably constant se- ries of parts. For example, there must be an ingoing nerve to carry in- wards a message or sensation from the outside world. This is the ''sen- sory'' nerve Of science. Then, there must exist nerve-center, or receiving office. as we may term it, whereat the message is received and from which it is reflected, or retransmitted, as we have seen. Lastly, there is need of a second or outgoing nerve which shall carry this reflected" message to muscles or other organs, as the case may be. This latter nerve, because the effect of its motion is to produce motion of one kind or another, is called the motor nerve. These three things are all that are necessary for the carrying out of our Efe's acts. DouEt- less there is much more that is complca in the details of reflex action. but it. essentials are as simple as 1 have de- scribed them. In this system of body telegraphy we see countless messages going in and out from nerve centers. ruling and controlling all the affairs of our existence. The body, in this view of matters, is a very busy state, whose officials are in perpetual and constant communication with their heads of de- partments,
 Finally it must be borne in mind that, while we arc conscious of much that we do, we arc also utterly unconscious of vast number of our actions. When we come to think of it, the fact of our re- sembling Messrs. Maskolyne and Cook figures, in some respects, is a tremendous advantage to us. We have ] not to think about every act of life; henco we arc saved much intellectual 1 wear and tear. Reading and writing, and piano playing, and walking and 1 many complex actions, may be and are performed entirely without the neces- ! sity for thought. Getting any thing off by heart" as the schoolboy puts it, 1 is really converting something which ! at first cost intellectual effort into | which is purely automatic In its nature; and the things which are most machine-like in our actions are just those which are most purely "re- Aex" in their nature. The Indian ] thief tickles the sleeping man with a straw, and causes him, in his sleep, to roll over on his pillow so that the va,uables beneath his head may be ab- stracted. This may be an illustration of nefarious conduct; but it is, none the less, an excellent example of reflex action unconsciously performed when human nature lies still In the silker bonds of death twin-brother, sleep" London News.