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Viewing the country from an eminence, the conical hills of granite seem to rise abruptly from a wooded plain. In crossing this plain, however, it is found hollowed into many small valleys. In the low country the granitic formation is everywhere is smoothed over by sedimentary or alluvial (for I know know not which term to apply) subaqueous

[in margin:] different matters.

[in margin:] King George's Sound

[in margin:] Compare with C. of Good Hope

[in margin referring to lines 6-18:] (& keep these pages for Cleavage & Concretions discussion)

The most abundant variety is an ochraeceous, honey-combed fine sandstone, abounding with iron (seldom having a metallic lustre) and quite similar to one of the varieties found at the Cap of Good Hope. The iron in this case shows a constant tendency to form a net work, enclosing earthy matter less forming aggregated together. Fragments of quartz and sandstone are often included in this stone, but the structure of the latter, I believe is deceptive. In the sandstone of the Blue Mountains, (near Sydney) thin seams of ferruginous matter, which appeared to be the remains veins of segregation, and not of subsequent infiltration, were common. These in some parts became so numerous, that the ordinary sandstone merely filled up the intersticial spaces in, and the rock, which from being weatheringed had in these parts assumed an angulo-vesicular surface. If the seams of iron had been less defined in their forming forms, the included patches of ordinary sandstone would have given a speudo-brecciated structure to the formation, very similar to that of in the superficial deposits we now are describing at King George's Sound.

In the island of Chiloe on the west coast of S. America, I found in a sandstone formation, very many perfectly spherical ferruginous concretions, of the size of a common shot, and absolutely undistinguishable from them, tThese centres of which were either partly hollow, or more commonly filled with loose sand. Here, and many other similar cases might be added, we see a common the same tendency in the atoms of iron either to form separate shells seam for the →

[in margin referring to last 9 lines:] Keep for cleavage discussion

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Separate shells & the

a irregular reticulations which may be considered as many shells intersecting each other modifications of one structure. In every country and in various formations innumerable instances occur of the atoms of carbonate of lime, and of magnesia, of silica, and alumina, being drawn together towards certain points, forming solid globular concretions; according therefore to all analogy we ought to look at the loose sand in the ferruginous sandstone as having been [blank filled by Darwin in pencil: 'attracted'] attracted together, and the hydrate of iron, as the residual matter left in the interstices. This view however is evidently inadmissible, for from the much greater chemical attraction, which has united the iron, often giving to it a metallic lustre 2nd from the transition from alefaised seams or veins of segregation in an irregular network, and lastly from the occurrence of such regularly formed and isolated shells like those from Chiloe, in which (where the shell like a vein, differs from the matter on both sides of it) like those from Chiloe. Within & without The cause why the law of aggregation of the iron, disseminated through any formation, should be being different, from that of so many other substances, I am unable to form any conjectures appears to me, a circumstance difficult to be explained— [remainder of page excised]

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