ABSTRACT
Boys and men who do not live by hard manual labour require a large amount of exercise in pure air in order to keep them in the highest possible state of health and vigour. The tendency of the population to congregate in large towns, the multiplication of artificial means of transit, the increased strain and competition of modern life, the calamitous change, by which business hours have begun and ended later, till crowds of sallow clerks are now released from offices after the expiry of daylight for many months in the year, are all causes antagouistic to this prime necessity of a nation which is to be long vigorous. It is true that, owing to improved drainage and purer water, to better food and ventilation, and to increased knowledge of medicine, the average length of human life has risen.
