29 



suddenly becomes less common amongst them ; since it is- 

 retained by men down to the extremes of life, consumption 

 loses little, if any, of its virulence among elderly males. 



To ask the question whether this is special to phthisis, or 

 common to disease in general seems absurd, for we find that 

 during four years 3,857 females died from all diseases below 

 the age of 15, 1,425 from this period up to 45 years, and 1,215 

 beyond this age ; or 1,425 during the reproductive period, and 

 5,072 at all other ages, a ratio of 1 to 3^ instead of 3^ to 1. 



But we may still inquire whether the table giving the 

 percentage of deaths to the population confirms the proposi- 

 tion deduced from the table of absolute deaths. Without 

 entering into all the particulars, we may say that it is con- 

 firmed in every point. The deathrate among the females per 

 thousand of living population from 10 to 15 is "41, from 15 to 

 20 it is 1'27, more than three times as great. This is the 

 sudden rise on the accession of puberty in the female. From 

 40 to 45 it is l - 37 ; from 45 to 50 it is "84, a considerable fall 

 at the cessation of the reproductive function. The rate from 

 15 to 45 is 7'7, for all other ages only 1*4, or 4 - 5 times as 

 great. The rate from 45 to 75 is 4 - 2, or only a little more 

 than half that of the reproductive period. Among the males 

 the rate from 10 to 15 years is "16, only a slight increase over 

 that of "09 from 5 to 10, when compared with that among 

 females, viz., from *079 to '41, explained by the existence of 

 puberty among girls under 15 much more frequently than 

 among boys. Prom 15 to 20 years it is "77, a great advance 

 over the rate of '16 from 10 to 15, concurrent with the setting 

 in of puberty among the great majority of males. From 15 to 

 45 years it is 6 - 9, at all other ages 2 - 9, or only 2 - 4 to 1, instead 

 of 4"5 to 1 among the females, corresponding with the absence 

 of any limitation of procreation among men. Prom 45 to 75 

 the rate is 8 - 5 per thousand, an increase over that from 15 to 

 45, and very different from the 4"2 per thousand among the 

 females, which is a decrease from that of 15 to 45 amongst 

 them, and presenting very boldly the different liability to 

 phthisis among men and women after 45 years, where the dif- 

 erence in regard to the reproductive function is so manifest. 



To 'test this theory, if possible, still further we may consider 

 males as almost certainly in possession of the reproductive 

 function from the age of 20 down to the extremes of life. 

 There were in the year 1876 53,044 men of this age, and among 

 them there' were 427 deaths from consumption. "Women we 

 may almost as certainly regard as procreative between 15 and 

 45,' of which age there were 44,971 persons in 1876, with 362 

 deaths in the five years. Here, then, we have the two classes- 

 »f eu'ch ages', that both are under the action of the one cause. 



