in South Australia. 173 



in the under crust without reaching the upper surface. The 

 crystalline portion would not be liable to decomposition Avhile 

 the latter woidd. Let ages do their work then on the uncrys- 

 tallised portion, and the strata will become decomposed into 

 surface soil, and so disappear ; but the really altered rock would 

 be unaffected, except, perhaps, rounded and weather-worn, and 

 would stand out in ridges of boulders. Upheaval now begins, 

 at a centre a little removed from them, and they become broken 

 from the under-pressing force, much more, of course, in pro- 

 portion as the upheaval is greater, and then we have the bands 

 precisely in the state in which we find them now. Be it 

 observed, that everything bears out this view. For in the first 

 place, the soil has formerly been composed of slate. Fortu- 

 nately the plough has never yet broken the turf, and we have 

 but to dig a foot or two to find the truth of this. The soil on 

 being uncovered, shows the former marks of stratification as 

 plain as possible. Again, the bands are broken smaller in 

 proportion as they go over a higher ridge. 



But as to the cause of the crystallisation, I know great excep- 

 tion may be taken. It may be said that on the supposition of 

 parallel cracks, I am calling to my assistance phenomena that 

 have never been observed elsewhere. This is true. But are 

 not these appearances in question such as have not been ob- 

 served elsewhere ; and are we not as yet in ignorance of the 

 greater portion of geological phenomena in the world ? And 

 to answer all objection, let me say that here are appearances 

 (the bands), which are clearly not dykes, nor due to anything 

 that in our present state of geological knowledge we can ac- 

 count for ; and I only take upon myself to say they might be 

 caused by such or such an agent, at the same time showing, as 

 far as evidence goes, my theory is borne out. If, notwith- 

 standing everything, I am not correct in my views, at least it 

 will be admitted that a cause has been in operation which we 

 are not cognisant of, and it is some slight advantage to geology 

 to know that there are more things in the earth's crust than its 

 present philosophy can account for. If it can be shown, how- 

 ever, that the upheaval was prior to the crystallisation, then my 

 theory falls to the ground. But nothing seen supports such a 

 view. It is true that some of the hills which are the very 

 highest (where their height, if they existed previously, would 

 keep them more out of the reach of subterranean agents) 

 the bands are less crystalline and sometimes unaltered, but this 

 is occasionally observed in the bands of the valleys, and again in 

 some very high hills they are the most completely crystallised of 



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