WM. H. WELCH, M. D. 53 



able as they may be for protecting the calf against the diseases 

 of cattle do not protect the infant against the diseases of the 

 human being. We have the most satisfactory experimental evi- 

 dences that the milk contains immune substances which have 

 been generated in the body of the mother, and see how impor- 

 tant it is that she should transmit these protective substances 

 to the offspring at this period of life when the offspring is 

 attempting to adjust itself to these new conditions and is ex- 

 posed to all these changes. This kind of protection is needed 

 particularly in the class of diseases which I have specified, the 

 acute respiratory and diarrhoeal infections and the infections 

 which are most preventable. Professor Fisher has made inter- 

 esting investigations, which he himself would not consider to 

 be anything more than approximate, but they are certainly sug- 

 gestive as to what is the ratio of preventability of these various 

 diseases of childhood and infancy. At least 60 per cent, of this 

 class of diseases is preventable, and readily preventable, by the 

 application of knowledge already in our possession. With fur- 

 ther additions to knowledge, the ratio of preventability would 

 be still further increased, but at present we probably are within 

 entirely safe bounds to say that 60 per cent, of the deaths of 

 infants in the first year of life due to the causes which I have 

 mentioned could be prevented. 



It will be the purpose of this Association to point out in con- 

 siderable detail what the causes of these preventable diseases 

 are and the measures which are to to be taken for prevention. You 

 cannot have the most cursory reference to the subject of infant 

 mortality without having at once brought to one's attention the 

 fundamental importance of maternal nursing in preserving the 

 life of the infant. That will be repeated over and over again. 

 I think that those in the audience who are familiar with the 

 subject only in the families of the well-to-do can hardly realize 

 the risks in artificial feeding. It is not because artificial feeding- 

 is not possible. It is possible we all know, but it requires an 

 amount of care and education on the part of those entrusted 

 with it which is not to be expected in the families of the poor. 

 It is not surprising to hear that the deaths are at least 15 to 1 

 among the artificially fed, as compared with those fed at the 

 breast. 



I had intended to speak further along somewhat similar lines, 

 but, as I have said, our time for keeping you here has passed, 

 but I would like before sitting down to point out what I conceive 

 to be certain of the useful functions of this Association. Of 

 course, one of the most important is the education of the public, 

 the enlightenment of the public. The responsibility is with you; 



