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for instance, we drop a line from any 

 of the Northwestern States, as Idaho, 

 Montana, or Minnesota, we find no uni- 

 form results, and if we go South from 

 the Dakotas we will find that the pro- 

 portion of the insane actually increases. 

 The notable increase when we strike 

 the Pacific slope I will speak of later. 



If we now attempt to explain this 

 condition of affairs by the topographical 

 or the climatic conditions we are at once 

 met by insuperable difficulties. If va- 

 riation in temperature is alone responsi- 

 ble, why does not the proportion of in- 

 sane diminish as we go south from the 

 Dakotas as well as from the New Eng- 

 land States? Or, on the other hand, 

 why should Maine have a smaller pro- 

 portion of insane than any other New 

 England State? Montana, which is as 

 far north as Maine, has a higher ratio 

 than the states immediately south of it. 

 If meteorological conditions are deter- 

 mining factors, why do we not find a 

 marked variation in the proportion of 

 the insane in the states bordering on 

 the Great Lakes ? Here we have con- 

 ditions quite different from anywhere 

 else in the United States. This region, 

 a large area of which is occupied by 

 these immense island seas, is directly in 

 the course of the greater proportion of 

 storms which come from the Northwest 

 and pass through here on their way to 

 the Atlantic coast ; sudden variations in 

 temperature, barometric pressure, and 

 wind velocity are the rule, and with the 

 immense areas of evaporation, fogs and 

 rains are frequent and the percentage 

 of cloudiness unusually high (66 per 

 cent), still there is nothing in the pro- 

 portion of the insane to call our special 

 attention to this region. 



I might continue in this wise, but it 

 is only necessary for me to call your 

 attention to the general results of such 

 reasoning. They are these. The varia- 

 tion in the proportion of insanity in the 

 different states is regular and uniform, 

 while both geographic and climatic con- 



ditions are not, but, on the contrary, 

 differ greatly in different parts of the 

 United States, as, for instance, in the 

 region of the Great Lakes just men- 

 tioned. If, therefore, we would explan 

 these figures, we must seek a cause as 

 uniform as its effects. This cause, or, 

 more properly, these causes, are the 

 same causes that make for civilization, 

 the same that make for permanency and 

 organization of social institutions, the 

 same that make for concentration of 

 population in great cities, the same, in 

 short, that make for progress in its 

 broadest sense. 



Before proceeding to the elucidation 

 of this proposition, let us for a moment 

 return to the consideration of some first 

 principles. 



I did not intend to convey the idea by 

 the remarks I just made about the in- 

 fluence of climate on conduct that no 

 such influence could be demonstrated. 

 On the contrary, I think it can be, and 

 in fact has been. Dexter * has recently 

 shown this in a most admirable and ex- 

 haustive study of the effects of climate 

 on different phases of conduct. For in- 

 stance, his studies show that as humidity 

 increases assaults, necessity for prison 

 discipline, and the number of arrests for 

 insanity decrease, while the data also 

 show an increase in these same occur- 

 rences when the barometer is low. 



Granting for the nonce that these 

 various meteorological conditions could 

 actually produce insanity, they could 

 not account for the uniform variation of 

 the proportion of the insane in the dif- 

 ferent states to which I have called your 

 attention . Weather changes are transi- 

 tory, and conditions that are inimical to 

 mental health are quickly followed by 

 others that are highly beneficial. This 

 is especially true of those regions of the 

 United States where the proportion of 

 insanity is high. The ratio of insane in 



* Edwin Grant Dexter, A. M. : Conduct and 

 the Weather. Psych. Rev., Vol. II, No 10, 

 May, 1S99. 



