SECTIONAL TRANSACTIONS.— I. 409 



family and the rate of reproduction are all important factors in determining 

 infant and child death-rates, and death-rates both from maternal and all 

 causes in mothers. In the early stages of the decline in the birth-rate, 

 most of the decrease took place in biological groups with very high death- 

 rates, and a decline in infant death-rate accompanied the fall in the birth- 

 rate. Latterly, much of the decline has occurred in groups with low death- 

 rates, so that the total infant death-rate may become stationary or even rise. 

 The decline, however, has mainly tended to cause the groups with high 

 still-birth and high maternal mortality rates to become a larger proportion 

 of the total. The apparent stability of these rates therefore probably hides a 

 real decrease in the individual groups. Although among all the women of 

 the age under consideration in the area, deaths from maternal causes con- 

 stituted only about 10 per cent, of all deaths, while among the 30,000 they 

 formed about 50 per cent, of the total deaths, yet the total death-rate among 

 the reproducing women at each age did not exceed that among all women of 

 the same age, i.e. reproduction probably weeds out the unfit rather than adds 

 to the total death-rate. A high maternal death-rate will therefore be found 

 under bad social conditions where the unfit abound, and also under good 

 social conditions where other weeding-out processes are few. 



Within the individual groups, the influence of overcrowding as measured 

 by rooms per person appeared unimportant. (The influence of congested 

 areas as distinct from overcrowded houses could not be measured.) Despite 

 ten years' acute industrial depression the total death-rates among women and 

 children of the ages studied had fallen by 20 per cent, during that period. 



Afternoon. 

 Dr. G. E. Friend. — Indices of health (2.15). 



Prof. Dr. E. Atzler. — Die Bedeutung der Ernahrung fUr die Leistungs- 

 steigerung (2.45). 



Prof. S. J. CowELL. — The aims and methods of nutritional science (3.15). 



The science of Nutrition, as commonly defined to-day, covers such a large 

 part of the field of biological science that it is not surprising that its study 

 is being pursued by those with very varied training in very diverse surround- 

 ings. Physicians, physiologists, biochemists and pure chemists have con- 

 tributed to the recognition and identification of essential food constituents ; 

 physiologists and biochemists have probed more and more deeply into the 

 problems of food requirements and intermediary metabolism ; physicians 

 at the bedside and field workers among the populations of the world have 

 been searching for the signs of faulty nutrition and have been trying to 

 explain and correct them. All these activities have been linked together, 

 the work of one group inspiring that of another ; all have made possible the 

 rapid advance of the knowledge of nutrition. The practical interest dis- 

 played in the application of the recently acquired knowledge to human 

 welfare by those who have contributed most to the discovery of its ' funda- 

 mental ' principles, has been a striking feature of the development of 

 Nutrition as a special aspect of scientific study. 



General Discussion on Physiology and health (3.45). 



