396 W. G. WOOLNOUGH. 
The author differs somewhat from Jutson in the ages 
assigned to these earth movements, and believes that the 
early or late Pliocene date assigned by that author to the 
Darling Peneplain should refer to the Meckering Level. 
The formation of the Darling Peneplain was older, while 
that of the Mount Dale Level may be as ancient as early 
Tertiary. 
EXPERIMENTS ON THE BEHAVIOUR OF IRON IN 
CONTACT WITH SULPHURIC ACID. 
By OC. EK. FAwWSITT, D.Sc, and A. A. PAIN, B.Sc., 
[Read before the Royal Society of N.S. Wales, September 4, 1918. } 
Two papers on this subject have already appeared.1 Com- 
paratively little research on this subject has been carried 
out, yet the matter is of great importance; the researches 
already published (loc. cit.) have therefore been continued. 
There are many peculiarities about the action of sulphuric 
acid on iron that have still to be cleared up, but we have 
confined our present experiments to two questions only. 
Part I.—A comparison of Iron in concentrated Sulphuric 
Acid with Passive Iron. 
Although iron is attacked very noticeably when first 
inserted into concentrated sulphuric acid, the action is 
much less vigorous after a few hours, and suggestions have 
been made by some chemists to us that in this case we 
may have to do with something resembling a “‘ passive”’ 
State of iron. We have therefore performed some experi- 
* Fawsitt and Powell, Journ. Soc. Chem. Ind., xxx11I, 234,1914; and 
Powell, Proc. Roy. Soc. N.S.W., xtvu, 59, 1918. 
