1910-11.] Incidence of Mortality from Pulmonary Tuberculosis. 357 
Mortality from Tuberculosis of the Lungs according to Sex and Age . — 
In Table III. the statistics for Scotland and England are compared. As the 
age periods in the English statistics are taken as ten years after the age 
25, the Scottish statistics have been tabulated in the same way. In both 
countries there has been a decrease in the mortality at each age period. 
Mortality among Males. — In Scotland the maximum mortality was at 
age 20-25 years in the four decades 1861-1900. In 1901-5 it was at age 
25-35, and in 1906-7 at 45-55. In England and Wales the maximum rate 
has always been later than in Scotland. In the three decades 1861-90 
it was at age 35-45, and from 1891-1907 it has been at 45-55 years. As 
in Scotland this postponement has been gradual. 
Mortality among Females. — In Scotland the maximum mortality 
coincided with that among males in 1871-80 at 20-25 years. In 1861-70, 
and from 1881 to 1907, it has been at age 25-35 years, and, as a rule, at age 
25-30 years. In England and Wales the maximum rate was at 25-35 
years from 1861 to 1890, and from 1891 to 1907 it has been at 35-45 years. 
The curves of these mortalities, which are plotted out on Plate I., show 
graphically the comparison between the sex and age incidence of the 
mortality in the two countries. 
Percentage Reduction of the Mortality in each Sex at Age Periods . — 
Taking the mortality rate in each sex and at each of the age periods 
during 1861-70 as 100, the amount of reduction at each period has been 
calculated as a percentage. For example: — The mortality in Scotland 
among males 0-5 years was in 1861-70 15, and in 1906-7 it was 4*38. 
The reduction is 10*62 per 10,000, i.e. 70*8 per cent. These percentage 
reductions in Scotland and in England and Wales are plotted out as curves 
on Plate II. 
Reduction of Mortality among Males. — The reduction at ages 10 to 45 
years has been smaller in Scotland than in England and Wales. Above 
45 years it has been greater. 
Reduction of Mortality among Females. — In both countries the reduc- 
tion among females 0-5 years has been greater than among males. In 
England and Wales the reduction in female mortality at age periods 5-10 
up to and including 45-55 is greater than in Scotland, with the result that 
while in the former country in 1861-1870 this mortality was lower than 
that in Scotland only from 0-5 to 20-25, in 1906-7 it was lower, from 0-5 
to 45-55 years. 
But there is a still more striking difference between the two countries. 
In England and Wales the reduction is greater in female than in male 
mortality from 15-20 years onwards, while in Scotland this is the case 
