342 TRANSACTIONS OF SECTION B. 
4. The Influence of Substituents on the Velocity of Saponification of 
Phenyl Benzoate. By Dr. H. McCompin. 
5. The Colouring Mallers of certain Marine Organisms. By Dr, A. Hou. 
The colouring matters of Diazona viridis and Syntethys Hebridicus have 
been shown to be due to a green body very similar to chlorophyl, and a purple 
substance which appears to be a dibromindigo. This purple compound is only 
found on the surface of the Ascidian Colony, and it is concluded that it acts as 
an oxygen carrier, since when the organism is alive and healthy it is not pro- 
duced. Under these conditions it would be maintained as the colourless leuco 
body, but with the death of the colony changes in metabolism take place and 
oxidation produces the colour. The green pigment is very possibly due to a 
symbiotic alga. ‘These pigments have been compared with those obtained from 
different species of A/urex and from Bonellia. 
6. The Corrosion of Iron and Steel by Arlesian Walers in New South 
Wales. By Professor Fawsirv. 
7. The Use of Waste Gases of Combustion for Fire Ealinctive and 
Fumigating Purposes. By Dr. G. Haren. 
The experiments of Clowes and Feilman on the extinctive properties of 
flames have shown that the flames of ordinary substances are extinguished 
when the oxygen in the atmosphere is reduced to about 15 per cent. The 
extinction of solid material, as for example ignited coal, requires a lower per- 
centage of oxygen, and takes time owing to the need for a cooling effect. Flue 
gas from ordinary boilers burning coal or coke does not generally contain more 
than 9 or 10 per cent. of oxygen, and if pumped into a space so as to displace 
the air will render the atmosphere fire-extinctive and will also be destructive to 
rats and other vermin. For practical purposes the flue gas must be cleaned and 
cooled before use, and formaldehyde vapours are sometimes added to it. 
Several installations making use of this process are now in operation. 
8. Lhe Hxtraction of Radium from Australian Ores. 
By 8. Rapcuirr. 
(1) A short account was given of all known occurrences of radioactive minerals 
in Australia. 
_ (2) The methods now in use at the Sydney works of the Radium Hill Co. for 
the extraction of radium from the complex ore found at Olary, near Broken Hill, 
were described. 
(3) The results of an examination of the various radioactive precipitates 
separated in the course of the works operations were given, together with the 
methods employed in working up preparations of ionium and actinium. 
J. The Inversion of Cane-sugar by Acids in Water-alcohol Solutions. 
By Georcu J. Burrows, B.Sc. 
The rates of inversion of cane-sugar by hydrochloric acid and sulphuric acid 
have been determined in water-alcohol solutions up to 75 per cent. alcohol. 
In both cases a minimum velocity has been found for a solution containing 
about 50 per cent. alcohol by volume. From the results obtained it is evident 
that the velocity of inversion is not proportional to the concentration of hydrogen 
ions in such a series of solvents. The similarity between the curve representing 
the variation of the inversion velocity with the composition of the solvent and 
the viscosity curve for these mixtures led the author to conclude that the rate 
of catalysis by acids is a function of the fluidity of the medium. 
The results for the inversion velocity show that the latter is not directly 
