no THE POPULAR SCIENCE MONTHLY. 



important change is completed. Immediately after this point is 

 reached, when the yearly increase in weight and height "begins to 

 diminish rapidly, the sickness-curve again rises very fast. The 

 most healthy of all the years of youth is with boys the seven- 

 teenth, which is also one of the two years of most active growth. 

 The eighteenth, on the contrary, which follows immediately 

 upon the attainment of puberty, appears to be a very unhealthy 

 year. 



All this indicates undoubtedly that during the period of weak 

 growth which precedes the coming on of puberty, and during 

 which our pupils are passing through the preparatory or lowest 

 classes of the middle schools, the power of resistance of the youth- 

 ful organism against external influences is diminished. During 

 the period of development of puberty, on the other hand, when 

 the youthful life is approaching maturity with all its swelling 

 force, the capacity for resistance rises from year to year, and the 

 liability to illness falls, reaching its minimum in the last year of 

 that period. Immediately afterward sets in another period of 

 diminished capacity for resistance, which usually includes the last 

 years of school life. 



Among the school girls, the future mothers of generations to 

 come, investigations instituted in thirty-five schools with three 

 thousand and seventy-two pupils brought out a fearful amount 

 of illness. Sixty-one per cent of the whole, all belonging to the 

 well-to-do classes, were ill or afflicted with serious chronic dis- 

 orders ; thirty-six per cent were suffering from chlorosis, and as 

 many from habitual headache ; at least ten per cent had spinal 

 disorder, etc. Such a condition of health in Swedish girls, grow- 

 ing worse in the years preceding puberty and during its begin- 

 ning, while it is not notably improved in the last, years of the 

 period, certainly deserves careful attention. The explanation of 

 it is easily found in the method of instruction for girls as a whole, 

 and in the organization of girls' schools after the pattern of boys' 

 schools. The amount of work, sitting still, etc., exacted of the 

 girl is not consistent with her health during her growing time. 

 Without going into particulars as to the influences injurious to 

 the health of growing children which proceed from their homes 

 or may be brought out in connection with the school and school- 

 work, it is still manifest that the burden of work which children 

 have to bear under present school regulations far exceeds what is 

 permissible, and is to a large extent responsible for the liability of 

 school children to illness. 



The average time daily demanded by the school for work in 

 class and at home is, according to the gymnasial schedules, seven 

 hours in the lowest classes ; and it rises rapidly and constantly, 

 till in the upper classes eleven or twelve hours are required. As 



