6Q 



took place during the deposition of the Drift to the extent of 

 something closely approaching 800 feet. By directing atten- 

 tion to this fact, I do not mean to infer that the formation 

 ever attained a thickness of 800 feet in any part of the neigh- 

 bourhood referred to, but that a steady oscillation of land and 

 water to that extent over the area has taken place so recently, 

 geologically speaking. This view harmonises in a marked 

 degree with Dr. Croll's cosmical theory of the glacial epoch of 

 the northern hemisphere, and was applied by me as originative of 

 the Australian Drift period (see Transactions of the Adelaide 

 Philosophical Society, 1878-9, pages 65 and 66). 



Quaternary. 

 This formation embraces a considerable portion of Murray- 

 street, the lower portion of the site of the town, the greater 

 portion of the Park Lands, and also detached areas, as exhibited 

 in iSpring Grully, Cockatoo Creek, AVTiitlaw Gully, and North 

 and 8outh Para Eiver. 



Soils and Subsoils. 



Alluvial. — The site of the greatest part of this description of 

 soil about Gawler precludes its fullest utilization for garden or 

 other productive purposes. 



Drift. — Soils derived direct from this formation are chiefly 

 confined within the limit of the site of the town, therefore they 

 are also of little or no agricultural or horticultural value. 



Miocene. — The soils of Gawler, which have been chiefly de- 

 rived from the waste of the underlying Miocene rocks, ])resent 

 a kindly character and greater adaptability to the growth of 

 the native pine and kindred species, shrubs, &c., than either 

 the soils of the Drift proper, or those immediately derived from 

 the fundamental rocks. To the north-east of this tract, 

 throughout the sub-division of Western Barossa, known as the 

 Concordia District, the surface outlines of the country are 

 undulating, and the soils and subsoils of a mixed character ; 

 the ]iill-to])s being covered with soils — including many quartz 

 pebbles — which have evidently been derived from the waste of 

 pre-existing Miocene beds, whilst the adjoining flats — the beds 

 of which, since Miocene times, have been denuded below the 

 horizon of the fundamental rocks — are now covered with soils 

 and subsoils derived from both formations. On my examina- 

 tion of this part of the district I was impressed with the idea 

 that the soils and subsoils of the flats were outliers of the true 

 Drift ; but on further consideration, after having revisited the 

 locality, I have satisfied myself that they are chiefly of a sub- 

 aerial wash from the adjoining slopes. 



Fimdamenfnl BocJcs. — On the south of the Gawler Miocenes, 



