The advent of puberty with the female sex differs according to the individual, the climate and the mode of life. In the torrid zones it sets in as early as the ninth or tenth year, and sometimes one meets women of that age with their first babes in their arms; but they are faded when they have attained their twenty-fifth or thirtieth year.[81] In the temperate zones girls usually attain puberty at fourteen or sixteen years of age, in some cases later still. The age of puberty also differs with girls living in the country from those living in cities. Among the healthy, robust country girls who work hard, as a rule menstruation sets in later than among our poorly nourished, effeminate, ethereal young ladies in the cities, who suffer from over-excitement of the nerves. In the country puberty usually developes in the normal way. In the city its normal development is an exception, and not infrequently it is accompanied by various symptoms of disease that drive physicians to despair. Often physicians are obliged to say that the only certain cure would be marriage. But in many cases this cure cannot be applied, owing to the unsurmountable obstacles. All these factors show where we must seek a change. To begin with, we need a complete revolution in our educational methods. We need a system of education that takes both the physical and intellectual qualities into consideration. Furthermore, we need an entirely different mode of living and working. But both cannot be brought about except by a ~complete transformation of social conditions~.