INTRODUCTION TO SOCIOLOGY 73
Thus, while in the first period, from 1835 to 1858, under the regime of the small industry still sufficiently equilibrated, mental derangement is more or less fixed and confined within narrow limits of oscillation, it becomes larger and larger with the new regime, not yet organized into the large industry and the world- economy.
From the comparison of the different countries and the dif- ferent sections of each country, Quetelet has drawn the follow- ing conclusions : (i) In general, in the mountainous regions there are more idiots than in level regions, and on agricultural plains more than in towns. (2) Sex exercises little influence, the seasons much ; the summer months produce most insanity. Age, also exercises an influence ; between thirty and fifty years insanity reaches its maximum in France. This period, the most favorable to mental derangement, coincides, according to him, with that of the creation of the chief dramatic works.
However, we have seen, for example in England and Wales, that sex combined with the occupation, is in bad conditions, more influential in insanity of females ; these offer, then, less resistance to this disease. Among the social factors of insanity the economic and the sexual seem to have the most influence. For the remainder, the relations indicated by Quetelet preserve all their value. In all cases, the most important variations in the production of insanity follow naturally from the most variable factors, that is to say, from social factors, of which the inorganic and biological elements are, on the contrary, the most constant and stable.
The following table gives the proportion of insane per 1,000 inhabitants in certain countries, from the latest statistics I have received :
Brazil - - 1.25
Belgium, 1858 1.40
Belgium, 1899 - 2.20
Prussia - 2.21
France 2.37
England and Wales, 1859 l -9
England and Wales, 1901 3.03
Chinese immigrants in America 7.15
Italy - - 7.01
