48 THE POPULAR SCIENCE MONTHLY. 



stages in the growth of language can be again studied in inverse 

 order in diseases of language. In such disease the syntactical lan- 

 guage is lost first, the more primitive gesture language is retained 

 to the last ; and Prof. Preyer has shown in full detail the striking 

 similarity between the various defects and impairments of lan- 

 guage, and the stages of its acquisition in children. In the ar- 

 rested development of idiots we may observe a slow and gradual 

 growth of faculties which in their normal rapid growth are so 

 perplexingly interwoven as to make accurate analysis an exceed- 

 ingly difficult task. Again, we have continued in idiots traits 

 appearing in certain stages of child growth, but later outgrown ; 

 as, for example, a tenacious but mechanical memory, a delight in 

 striking sense-impressions, an accurate mimicking of surrounding 

 noises, a love of teasing and torturing animals, and the like. 

 Finally, in hypnotism, in which condition we have a withdrawal 

 of control by higher centers, a reduction to a more primitive grade 

 of mentality, we see analogies to childish traits ; the vivid imagi- 

 nation, the complete absorption of the mind of the subject in the 

 one suggested act or object, his ready suggestibility, his keen per- 

 ception and accurate mimicry, may perhaps indicate the line of 

 thought here pertinent. Any and all such analogies may be easily 

 carried too far, but essential and significant points of community 

 may be traced without falling into this error. 



I have thus attempted to lead the way through some of the fields 

 in which modern psychologists have reaped a valuable harvest, 

 and from which they expect a still richer fruitage as the result of 

 a more thorough cultivation. To such of my readers as may feel 

 that they have been hurried over the ground and allowed glimpses 

 when protracted study would alone suffice, I can only offer the 

 excuse of the professional guide, that there was much to show in 

 a limited time. Those who may feel that they have been asked to 

 consider things quite trivial and familiar, must take comfort in Mr. 

 Bagehot's words that " small things are the miniatures of greater/' 

 and that my purpose has been accomplished if I have succeeded in 

 freshening " their minds by object-lessons from what they know." 



Depaetment M— of Ethnology, Archaeology, History, Cartography, etc. — of 

 the Columbian Exhibition has been given one hundred and sixty thousand square 

 feet of space in the gallery of the northern half of the Manufactures and Liberal 

 Arts Building, together with a strip of land a thousand feet long and from one 

 hundred to two hundred feet wide, along the border of the lagoon in the south- 

 eastern part of the grounds. Here the groups of native American peoples will be 

 arranged geographically, and will be living under normal conditions in their native 

 habitations during the six months of the Exposition. The scheme of classification 

 of the department, as given in detail by the National Commission, covers a great 

 diversity of subjects. 



