592 THE POPULAR SCIENCE MONTHLY. 



ing. These are commonly spoken of as instinctive actions, but it is 

 impossible to separate them from the class last spoken of. A little 

 higher than the reflex actions are the truly instinctive ones, as a 

 type of which we may take the actions of some very young chickens, 

 experimented upon by Mr. Spalding. In a paper read before the 

 British Association, this experimenter says : "-Chickens hatched and 

 kept in the dark for a day or two, on being placed in the light nine 

 or ten feet from a box in which a brooding hen was concealed, after 

 standing chirping for a minute or two, uniformly set off straight to 

 the box, in answer to the call of the hen, which they had never seen, 

 and never before heard. This they did, struggling through grass, 

 and over rough ground, when not able to stand steadily on their legs. 

 Ao-ain, a young hawk was made to fly over a hen with her first brood 

 of chickens, then about a week old. In the twinkling of an eye most 

 of the chickens were hid among the grass and bushes; and scarcely 

 had the hawk touched the ground, about twelve yards from where 

 the hen had been sitting, when she fell upon it, and would soon have 

 killed it outright. A young turkey gave even more striking evidence. 

 When ten days old it heard the voice of the hawk for the first time, 

 and close beside it. Like an arrow frcm a bow it darted oflT in the 

 opposite direction, and crouched in a corner, and remained for ten 

 minutes motionless and dumb with fear." These examples will serve 

 as illustrations of pure instinct, and we wull pass now to actions which 

 are superior, but obviously similar, to the instinctive ones. Ac- 

 tions which are frequently repeated become habitual, and habits of 

 long standing become so firmly fixed that the actions are performed 

 unconsciously, and, as it were, instinctively. 



Most of us can remember the labor and pains which were required 

 in order to learn to write: the comparatively easy acquisition of the 

 art of making down-strokes, and the tendency, which we adhered to 

 so obstinately, to form all our letters with down-strokes, and to fill 

 in the curves and shading afterward. Any one who has watched a 

 child writing has observed the necessity under which it labors for 

 counting the bends to distinguish an m from an n, and the tax which 

 an hour's writing inflicts upon all its bodily and mental powers. Con- 

 stant practice soon renders writing habitual, and the necessary mus- 

 cles act mechanically, so that we are able to give all our attention to 

 the intellectual part of the process, while the writing is done without 

 any effort or attention. A well-drilled soldier performs the proper 

 evolution at the Avord of command, although he may be so preoccu- 

 pied or so fatigued as to be perfectly unconscious of his actions. 

 Such habits are remarkably persistent, especially when they are ac- 

 quired early in life, and they have nothing to distinguish them from 

 instinctive actions except that they are unconscious. 



They are often performed involuntarily, and even in opposition to 

 a previous determination. Street-car horses soon learn to stop and 



