XIV. 
ABSTRACT OF PROCEEDINGS. 
Abstract of Proceedings, 24th September, 1945. 
The Ordinary Monthly Meeting' of the Society was held in the 
Geology Department of the University on Monday, 24th September, at 
8 p.m., with the President (Prof. H. J. Wilkinson) in the chair. Thirty- 
three members and friends were present. The minutes of the previous 
meeting were read and confirmed. Mr. A. Millingen was elected to 
Ordinary Membership, and Mr. R. Riek, Mr. 0. T. Fenwick and Dr. S. 
Julius were nominated for Ordinary Membership. 
A paper on “A Marine Early Cretaceous Fauna from Stanwell 
(Rockhampton district) ” by F. W. Whitehouse, D.Sc., Ph.D. (Major) was 
read by Dr. W. H. Bryan. A small mulluscan fauna of early Cretaceous 
age was described from a bed at Stanwell that apparently is within the 
Stanwell Coal Measures. The fauna is typical of the Valanginian 
Trigonia beds of the Indo-Pacific region and, with other evidence, makes 
the Lower Cretaceous history of Eastern Australia very closely parallel 
with that of India and of East and South Africa. From this evidence 
it would appear that the Stanwell Coal Measures are later than has been 
thought, being equivalent to the Blythesdale (pre-Aptian Cretaceous) 
and not Walloon (mid to late Jurassic) Series. This is not at variance 
with the floral evidence. 
A symposium on “ Potability of Water” was held. The first speaker, 
Mr. C. Ogilvie, traced ground water through its course, stressing the 
investigational importance of soaks and springs, and briefly reviewing 
the theory of encroachment of sea water. Typical analyses of ground 
waters were then considered, and reasons were put forward, based on 
artesian statistics, for his opinion that a substantial proportion of the 
chlorine in ground water is of connate origin. 
Dr. W. J. Chamberlain stated that modern water purification plant 
comprises facilities for coagulation, sedimentation, filtration, chlorina- 
tion and correction of acid water. In coagulation for removal of 
suspended solids, adequate mixing after distribution of the applied 
coagulant — generally aluminium sulphate — is imperative if economical 
treatment is to be expected. Mixing periods of 20 to 30 minutes are 
essential, with velocities ranging from 0*6 to 2-0 feet per second. The 
sand of filter beds is not a true filter in itself, but serves as a framework 
upon which the actual filtering medium is imposed — in slow sand filters 
this , medium is a natural biological growth of algae, diatoms, zoological 
material, &c., in rapid filters part of the “floe” formed in coagulation 
is carried over to film the sand. Modern practice combines ammoniation 
with chlorination, whereby chloramines are formed. These compounds 
are efficient bactericides and much more stable in water than free 
chlorine. By their use chlorine may be carried throughout the distribu- 
tion system and after-growths of bacteria controlled. Correction against 
acid water is carried to the point of saturation to calcium carbonate by 
addition of soda ash. 
Mr. C. R. von Stieglitz drew attention to the fact that the figure 
for total soluble solids was not a satisfactory criterion to use in assessing 
the quality of water for irrigation and that consideration should be 
given to the percentage composition of the various basic ions expressed 
m Ca -f- Mg 
as milligram equivalents. The use of the formula ~ (where 
the bases are expressed as milligram equivalents) to assess quality was 
explained, and it was stated that when this ratio fell below 0-5, the 
