430 Correspondence — J. Wilfrid Jackson. 



the Karroo dolerites. The Umkondo formation is referred by 

 Mr. Mennell to the Waterberg, which it resembles litbologicallv. 

 The Karroo system covers a good deal of ground in Rhodesia, but no 

 tillite has been found. The age of the red sandy Kalahari Beds is 

 still uncertain : they represent a period of very arid conditions at 

 some time between the close of the Stormberg and the present day : 

 it is impossible as vet to be more definite than this. 



E. H. R. 



OOIRRESIFOISriDIEirsrCE. 



A QUAETZOSE CONGLOMEKATE AT CALDON LOW, STAFFS. 



Sir, — In the August number of the Geological Magazine, p. 384, 

 Mr. F. Barke, Chairman of the Geological Section of the North Staffs 

 Field Club, states that the quartzose conglomerate recently described 

 by us (Geol. Mag., February, 1919, pp. 59-64) "was discovered in 

 1905 by members of the Geological Section of this club, and the fact 

 recorded in the Trans., vol. xl, p. 85, 1905-6 ". 



When our note was being written we had before us the article to 

 which Mr. Barke refers, and which reads: "In opening out the 

 new quarry at Caldon Low, on the eastern side of the hill, an 

 interesting section has been exposed. The beds of limestone dip 

 steeply to the east, and are badly faulted ; traces of lead can be seen 

 in some of the fissures, and there were signs of old workings on the 

 side of the hill. At the southern end of the quarry occurs a lime- 

 stone breccia containing Bunter pebbles ; a swallowhole, now filled 

 with cave earth, has been cut across, communicating with a fissure ; 

 the latter is said to have been traced for a considerable distance down 

 the hill until the explorers were stopped by water — it has been 

 partially filled up by refuse from the railway cutting; towards the 

 northern end the limestone becomes deeply stained with haematite. 

 The beds are almost unfossiliferous ; amongst the fossils noticed were 

 Productus humerosus, Orthotetes crenestria (sic)." 



We fail to understand how the description given by us of the 

 position occupied by the conglomerate section can be made to agree 

 with the above-quoted statements. It may be observed that : — 



1. The quarry in which occurs the conglomerate section is situated 

 on the north-west flank of the hill, and not on the eastern side. 



2. The beds of limestone do not dip steeply east: the underlying 

 humerosus-limestones are pi'actically horizontal; the conglomerate 

 is obscurely bedded in its lower portion, while the upper beds dip 

 N.N.W. at an angle of 30°. 



3. No definite evidence of faulting is visible. 



4. The conglomerate extends round the north-east flank of the 

 Low from the north-east end of the quarry. 



5. Finally, the pebbles present do not resemble the typical 

 Bunter pebbles in general facies, while the presence of an abundant 

 and highly characteristic Upper Carboniferous fauna places them 

 very considerably earlier than Bunter times. 



Thus, we venture to think we were justified in concluding that 

 the breccia with Bunter pebbles recorded by Mr. Barke in 1906 was 



