August i, 1 885.] The Australasian Scientific Magazine. 9 
information as we journey along. Here, then, in the Tambo Valley, above 
Tongio, let us examine our surroundings. Are there no objects of interest ? 
Can we not find “A pleasure in the pathless woods ?” Yes my friend — 
even those steep spurs of silurian slate and sandstone may prove to us a 
lesson ; a lesson fraught with interest of the past. Here is a sideling 
cutting, see how the beds of sandstone and of slate alternate, and the whole 
series of strata is nearly vertical; but do you note those small strings 
and veins of quartz on the further side, there is evidently some change in 
the formation at this place, the slate also appears to be more finely 
laminated and acquiring a micaceous texture. Yes, we are now on the 
margin of a mass of metamorphic schists which extend right across the main 
divide to the westward, into the Livingstone Creek valley. The hills in 
front of us appear to present more rounded outlines, and the soil is altered 
m colour and character, it is now more sandy, and full of quartz grains ; 
and there is also a slight alteration in the species of trees, and in the 
presence of many endemic herbs and shrubs. Again here, is an outcrop of 
rounded greyish rock which stands out like a tor of granite, but it is not 
granite, it is stratified, and the lines of stratification is parallel with 
that of the slates and sandstones we have left behind us near Tongio, 
this is gniess, or, in other words, a rock which has been transmuted by 
powerful plutonic forces out of soft silurian slates and sandstones. Pres- 
sure and heat, with the chemical action of percolating meteoric waters on 
the components of the rock masses may have played the most important 
part in this transmuting process. We will not stop to discuss the various 
forces by which the alteration of these crystalline rocks has been effected. 
Suffice it for us to note that there is an undoubted passage from soft silurian 
slates and sandstones to mica schists and gneiss. But more of this anon. 
You ask how those rounded and flattened boulders were deposited on the 
point of the low spurs to the right of us, fully fifty feet above the present level 
of the Tambo River? Do they represent the course of the old river bed ? 
If such is the case, the river fiats must have been much more extensive 
than at present. Yes, this is the case, for if we cross the river you will find 
similar deposits on the opposite spurs at the same level, now separated by a 
distance of from two to three hundred yards, while the present river, where 
it winds sinuously through the alluvial flats is not more than ten yards wide. 
Here we have a geological problem to solve. Are these boulders deposits 
of fluviatile origin, or is it possible that the displacing agencies may be 
in any way connected with the glacial period of the latter? If the latter, 
are there any evidences in the shape of striated surfaces, or other proofs of 
glacial action? And in either case, to what geologic age do they belong? 
Are they tertiary or post-tertiary ? If the former, of what period are they? 
Eocene, nueocene, or pliocene deposits, etc. — perchance our examinations 
higher up the valley, nearer Bindi, may assist us in forming an opinion. 
Ah I You see a clear, rounded, grassy eminence ahead ot you, and the 
surrounding high ranges are receding — the country is becoming more open. 
But here is another sideling cutting. What is the formation ? It is that 
of mica schist, of rather coarse texture. A little further on and you will 
find another change in the country, a change which will bring you to the 
edge of the limestone formation, to the romantic area of Bindi. Once the 
bed of the ocean, now a lovely piece of mountain landscape; the scene of 
an industrious settlement, and for us the field for our progressive studies 
wherein we may glean some slight insight into the past history of this fair 
land in which we live. 
( To be continued. ) 
