Segar. — On New Zealand Health Statistics. 119 



persons under the age of 15 might, for most purposes, be 

 entirely neglected. Now, whereas the total population of the 

 colony increased between 1881 and 1896 by 43'8 per cent., 

 the population in some of the later age-periods considered 

 as much as trebled. Further, the number of people that 

 become insane in any age-period during any year, as repre- 

 sented in Table I., does not represent the number actually 

 insane in that age-period, for that number includes the sur- 

 vivors of all those belonging to that age-period who became 

 insane in previous years and failed to recover. Thus the 

 number of insane in any section of the people is cumulative 

 relatively to the population, and the number of insane per 

 10,000 of the population must increase rapidly in the age- 

 periods of maturity as we rise from one age-period to a higher 

 one. This is quite distinct from the liability of sane persons 

 at those ages to develope insanity, and, with the rapidly 

 increasing proportion of the whole population included in the 

 later age-periods, completely explains the continually growing 

 proportion of the population that are afflicted with insanity. 

 Considerations brought forward in the paper already referred 

 to, leading us to expect a continued rapid increase for many 

 years to come in the proportion that the old bear to the 

 whole population, also lead us to expect a similar increase 

 with respect to the insane, and this without the aid of any 

 increased liability of the race to insanity, and possibly even in 

 spite of a falling-off in such liability. 



Cancer . 



The statistics of cancer as commonly presented make it 

 appear that that relentless disease is increasing its ravages at 

 a rate that is somewhat horrifying. In the year 1879 there 

 were 118 deaths from cancer, forming 2-11 of the whole 

 number of deaths, and being at the rate of 2-63 deaths 

 per 10.000 of population, whilst in 1898 the number of deaths 

 from cancer was 471, forming 6-50 of the whole number of 

 deaths, and being at the rate of 6-40 deaths per 10,000 of 

 population. The number of deaths from cancer thus in- 

 creased some two and -a half times relatively to the population 

 during the period of twenty years under consideration. We 

 shall apply, however, the same kind of analysis as that just 

 used for the case of insanity ; and the results, though not 

 yielding a conclusion just the reverse of the popular notion, as 

 in the case of insanity, will still be found to considerably 

 modify the estimate generally formed of the progress of this 

 disease. 



Table II. presents the results obtained in the manner 

 already described. 



