total number of deaths is in itself a proof tliat the mortality-rate 

 has been lowered in the last two years ; I wisli rather to point 

 out tlie fact that there lias been a marked reduction, both abso- 

 lutely and relatively, in the mortality from the diseases selected 

 for consideration. While in the three years 1882-84 the deaths 

 from typhoid amounted to 4.18 per cent, of the whole, they 

 formed only 3-17 per cent, of the total mortality in 1885-86. 

 Again, in 1882-84 the diarrhoeal diseases were responsible for 

 10'44 per cent, of the total mortality, while in 1885-86 tliat per- 

 centage was only 7*3 7. 



These figures appear to show very satisfactory results, Ijut it is 

 necessary to admit that they may fairly be subjected to criticism 

 before being accepted as proof of the benefits follo^^dng sanitary 

 improvements. It may be alleged with reference to the lowered 

 death-rate from typhoid that it is simply due to the fluctuations 

 observed to occur in the prevalence of this disease. And with 

 reference to the diminution in the number of deaths from the- 

 diarrhoeal class of diseases, it may be insisted that the reduction is 

 the consequence of the lowered birth-rate, most of the deaths 

 from these diseases occurring among infants. 



These criticisms are fair, and must therefore l^e fairly met, and 

 that which applies to the lowered mortality from typhoid can, I 

 think, be fully met, though it must be admitted that the figures 

 referring to the diarrhoeal death-rate cannot be taken as very 

 conclusive evidence. The general validity of the conclusions may 

 be tested in the following way : — If the lessened mortality in 

 1885-86 was simply owing to accidental fluctuations, the result of 

 seasonal or other influences not clearly ascertained, then there 

 ought to have been a somewhat similar range of fluctuation in 

 other districts. For the purpose of discovering whether or not 

 this was the case, I have constructed the following table, the 

 figures in which apply to the whole of South Australia, exclusive 

 of the re o-ist ration district of Adelaide. 



When rates are calculated, as before, it appears that, while 

 typhoid caused 2*37 per cent, of the total moi-tality in 1882-84, 

 the percentage was 2*52 in 1885-86. In the two periods the per- 

 centage of the general death rate from the diarrhoeal diseases was- 

 10-19^iud 8-38 respectively. 



