•engine purposes, and tlie water derived is eminently suitable 

 for sucli uses, being clear and soft. 



AVhere the plain slopes up to the foot of the hills the red 

 <3lay or loam is found resting directly against the primary rock, 

 land the river channels where they debouche on the plain 

 ■•show only a section of this upper bed or the overlying sand 

 ;and travertine. Summarised, therefore, the strata of the 

 plain consist in descending order of — 



Blown sand 



Travertine 



Loam and red clay 



Sand and gravel, with brackish water . 



Blue clay ... 



264 feet 

 Quicksand and gravel, with abundance of good water. 



THE HILLS. 



The rocks composing the hill country are divisible into 

 three groups, each unconformable to the others. The newest 

 formation is a gritty sandstone, often a ferruginous conglome- 

 rate or breccia. The coarser portions occupy the lowest levels, 

 and from this the transition is a gradual approach to a lighter- 

 coloured and finer-grained sandstone, which forms a cap to al- 

 most all the ranges. No fossils have been detected in it, and 

 has been referred to various geological ages, from Miocene to 

 the Desert Sandstone. Extensively distributed, it is also very 

 thick. At Macaw Creek, south of Ehynie, it forms round- 

 backed hills 200 feet high. In the valley of the Light, between 

 Hamilton and Anlab}', it is also greatly developed. The most 

 ^extensive and unbroken series of it is met with on the Alma 

 range, where it forms a cap and flanking formation all the way 

 from Stockport to Saddleworth. As might be inferred, the 

 nature of this rock varies greatly, especially the upper por- 

 tions. In some places, as near Undalya, it is a coarse sott sand- 

 stone ; a,t Eh3^nie and west of Stockport it is quarried as a 

 vphite freestone for building purposes. At Stockport itself and 

 near Marrabel its ferruginous beds yield splendid tough road 

 metal. On the Marrabel range it is compact, gvey, hard, and 

 I)arely distinguishable lithologically from the grey quartzite 

 forming the core of the range. 



The best exposure of this series is seen at Stockport, on the 

 bank of the River Grilbert. There the western side of the 

 •channel is formed of very coarse conglomerate, consistiug of 

 quartz stones (some of them being as large as one's fist) 

 •cemented together by a ferruginous paste. The G-ilbert hai5 

 •cut a channel throusfh it, and nassins westward it is seen at 



