JOHN S. FULTON, M. D. 139 



In the third week of life enter four causes of death; the tuber- 

 culous diseases, whooping- cough, diphtheria and measles. The 

 tuberculous diseases cause their maximum mortality between 

 the sixth and eighth months; whooping cough in the fifth and 

 sixth weeks apparently, though the English experience seems to 

 indicate a secondary mode of mortality for whooping cough 

 toward the end of the first year. The mortality of measles 

 reaches its maximum at the end of the first year, and declines 

 but little through the second year. After the second year the 

 decline is quite rapid. Diphtheria mortality reaches its maximum 

 in the third year. A mortality from scarlet fever begins in the 

 third or fourth month of life and reaches its mode in the third 

 or fourth year, later than the mode of diphtheria. The tubercul- 

 ous diseases are distinguished from the four acute infections 

 by the occurrence of another mode in adult life. In this 

 respect tuberculosis resembles the three acute respiratory infec- 

 tions, though an important distinction is perceived in that the 

 adult mode of tuberculosis occurs early and is the major mode 

 for tuberculosis, while the adult mode of bronchitis and the 

 pneumonias is the minor mode and occurs in age. 



The four acute infections, whooping cough, measles, diph- 

 theria and scarlet fever, agree in the narrowness of their range 

 of fatality. They thrust a very thin edge into the neo-natal 

 period, they rise to their maxima very sharply, and their descent 

 is but little less abrupt. Their mortality is nearly all found within 

 the first five years, and they all cease to be significant factors in 

 the mortality or the morbidity of man before the twentieth year 

 is reached. The frequency of attack shows different time rela- 

 tions in all four cases. The morbidity mode for whooping cough 

 seems to occur about a year later than the fatality mode, per- 

 haps only a few months later. The attack mode of measles falls 

 on the fifth year, three years later than the mortality mode. The 

 attack mode of diphtheria falls between the fifth and seventh 

 years; its exact position being undefined, though well outside 

 the period of infancy. The attack mode of scarlet fever is 

 apparently in the sixth year. The time relations of morbidity 

 and mortality therefore, seem to remove measles, diphtheria and 

 scarlet fever from the period of infancy, leaving whooping cough 

 in a doubtful position within the frontier of infancy. Yet the form 

 of the whooping cough curve includes one suggestion con- 

 veyed by all these four curves that they are forced, on the side 

 toward birth, into conformity with some medium more resist- 

 ant than that on the side toward childhood. 



If there is a group of diseases causing a considerable infant 

 mortality and showing in their frequency curves, that their ap- 

 proach to infancy is somehow definitely resisted, it is important 

 to identify the causes of death thus halted on the margin of 

 infancy. Statistical evidence, measured by minor units of time, 



