ABSTRACT OF PROCEEDINGS. XXVil. 
towns from the time of Henry III. to that of Queen Victoria 
was briefly sketched. The mode of assessment in money 
value of lives saved by sanitary works was explained on the 
lines laid down by the most eminent authorities, and it was 
clearly shewn that the expenditure on these works was fully 
justified from an economic standpoint, and that the savings 
effected in money value amounted to about a ten years’ 
purchase of the various works. One notable economic effect 
due to sanitary works is the balancing of the losses in popula- 
tion due to the decrease of the birth-rate, which of late 
years has been of a serious character, and a diagram was 
exhibited showing this phase of the question for all the 
principal countries in the world and the principal towns in 
Australia. In addition to the diagrams already mentioned, 
the author exhibited diagrams showing the curves of popula-- 
tion and expenditure on water supply and sewerage works: 
for Sydney, Melbourne, and London, and a diagrammatic 
illustration containing all the information required for an 
exhaustive study of the question. 
A discussion ensued in which the following gentlemen 
took part:—Dr. R. Greig Smith, Mr. W. A. Dixon, Dr. I’. H. 
Quaife, Mr. W. E. Cook, and the Chairman. Mr. Cardew 
replied. 
2. “‘On the protection of Iron and other metal-work,”’’. by 
WILLIAM M. HAMLET, F.I.C., F.c.S.,Government Analyst. 
The author pointed out that the stability and permanence 
of the materials used in building construction depended on 
the application of a knowledge of chemistry and physics, 
and that the engineer, architect, and builder, must keep in 
touch with this knowledge in order to make the best use 
of the nature and possibilities of their materials; and just 
as the chemist seeks a knowledge of the structure and dis- 
integration of matter, so also will he know of the best means 
to adopt for the protection of materials against the wear 
