1038 PROCEEDINGS OF SECTION I. 
(b.) In no other disease has an abatement of the death-rate 
from any cause, sanitary or otherwise, taken place to 
anything like the same extent. 
(c.) Its mode of action is no longer mysterious or supposed 
to be contrary to Nature, but is shown by the light 
which bacteriology and experiment has thrown upon it 
to be one of several illustrations of a principle in Nature 
by which immunity from certain diseases is secured. 
(d.) Prior to the introduction of vaccination, small-pox was 
the scourge of infant and adolescent life ; in vaccinated 
communities to-day it is the adults who chiefly suffer 
from it. 
(ec) It has been clearly proved by experiment that revaccina- 
tion at a given age of 1) or 16 years, restores the 
protection to adults. 
(/) Even when adults who have been vaccinated in infancy, 
and who have not been re-vaccinated, are attacked by 
small pox, the disease runs a highly modified course. 
(This was my own experience at the age of 20.) 
(y) The consensus of opinion with respect to the use of 
humanised or calf lymph, is, that humanised lymph 
should be abandoned in favour of calf lymph. 
This, then, is the position of the vaccination question. For the 
security of the colonies, the law throughout Australia should be 
assimilated on a compulsory basis. For this, I presume, we must 
wait the awakening of the legislatures that still lag behind. 
I will not essay to weary you further. The contention is sus- 
tained that the essential weakness in Australian public health 
administration is the control of communicable diseases. Our 
death-rate in some of these diseases is even higher (see diagrams) 
than the death-rate of England, notwithstanding the favourable 
character of many of our conditions and surroundings. For 
instance, we are young communities, with preponderating propor- 
tions of youthful population. We inhabit a new soil, with spaces 
for air and settlement unknown in the old countries of Europe, 
while our climate must be said to be conducive to longevity. 
There is great need for amendment in the control of these active 
diseases. We undoubtedly make the mistake of following England 
in her efforts to establish a complete system of local self-govern- 
ment. I am not opposed to local self-government as a working 
principle, but I none the less regard the inclusion of the adminis- 
tration of infectious diseases, as outside its sphere. The light 
which science has thrown upon public hygiene is comparatively 
recent ; the principle of local self-government in England is very 
