574 THE POPULAR SCIENCE MONTHLY. 



effect upon the progress of any ailment requiring medical treatment. 

 This class of cases occupies a sort of disputable ground, a border ter- 

 ritory which scarcely permits of their being included in hand-books 

 of insanity, nor yet in the ordinary systems of medicine. They are 

 considered here among the aspects not as outcomes of disease, as are 

 the mental attitudes described in the earlier divisions of this paper, but 

 rather as mental conditions, not normal nor yet insane, which exercise 

 much influence over the progress and course of ordinary ailments. 



Finally, there is a condition of temporary, evanescent brain-impair- 

 ment, which is produced by acute disease, and especially by severe 

 attacks of fever. The mental faculties are usually somewhat impaired 

 by severe attacks of typhoid fever, and soldiers, after recovery from 

 such, are not put on sentry duty for months, as they are pretty certain 

 to forget the watchword and countersign. At other times, more 

 marked impressions are made ; certain acquirements are entirely lost, 

 or the mind may even become a smoothed tablet. Many curious in- 

 stances of such effects are furnished by Abercrombie, in his well-known 

 work, " The Intellectual Powers," and by Carpenter, in his recent work 

 on "Mental Physiology." Commonly enough, this passing condition 

 of brain-impairment is followed by an accession of mental vigor and 

 a condition of intellectual activity which remain permanently and 

 exercise an excellent influence over the after-life of the individual. 



The relations of body and mind are becoming much more compre- 

 hensible and better understood since Science has shaken off the incubus 

 of theological teaching as to the severance of soul and body ; that 

 baneful psychology is now thoroughly undermined ; the erroneous and 

 mischievous superstructure is cracking and gaping on every side, and 

 ere long the ground occupied by a crumbling ruin will be covered by 

 a gradually growing erection, based on a foundation of facts, and 

 reared by an expanding intelligence. 



-*- 



BIOLOGY FOE YOUNG BEGINNEBS. 1 



By SAEAH HACKETT STEVENSON. 



II. 



IN the chimney-corner by the kitchen-fire stood a quaint stone jar 

 that every winter morning bubbled over with the light, gray 

 foam of buckwheat-cakes. While our "mouths watered," our minds 

 wondered wondered at the magic by which so many cakes were 

 made out of so little flour. We believed there were fairies in the 

 yeast ; but it was only the other day that I succeeded in finding these 

 fairies, and I want to tell you how you may find them too. 



1 From " Boys and Girls in Biology," in the press of D. Appleton & Co. 



