114 Transactions of the South African Philosophical Society. 
south. In 1886,* in his report on the sub-Karroo coal, he called 
attention to the fact that the outcrops of the two types of con- 
glomerate—the undisturbed on the north, and disturbed on the 
south— are continuous along the western part of the Colony. 
Mr. Dunn inferred from this, and the occurrence of certain black 
shales, that the conglomerates were contemporaneously formed in 
the north and south; but up to the present time the evidence is 
not sufficient to prove this, and they may well have been still forming 
in the north while the Ecca beds were being deposited in the south. 
In the same report Mr. Dunn described the occurrence of a scratched 
floor below the conglomerate near the junction of the Orange and 
Vaal Rivers, and attributed the scratches to the action of floating ice 
driven over the floor of a lake. After 1886 there was nothing of 
importance published about the Dwyka conglomerate until last year, 
when Dr. Molengraaff + found and described some glaciated rocks in 
the Vrijheid district of the Transvaal; he concluded that the phe- 
nomena were only to be explained by supposing that land-ice 
traversed the district. 
The relationship between the Prieska glacial conglomerate and that 
known as the Dwyka conglomerate of the southern Karroo is still un- 
certain, and although we have no doubt that their outcrops are con- 
tinuous, the discussion of the question must be left until further 
evidence has been obtained. It is chiefly from Mr. Dunn’s use 
of the term ‘‘ Dwyka conglomerate ”’ that it has been applied to any 
conglomerate lying‘at the base of the Hcca beds or rocks supposed to 
represent them, but the evidence for the correlation of the beds in 
different parts of South Africa has not yet been sufficiently dealt 
with. In this paper we shall not use the name Dwyka conglomerate 
in reference to the Prieska rock where our own observations are con- 
cerned, but it is retained when the observations of others, who do so 
employ it, are mentioned. 
The object of the present paper is to describe certain sections of 
the conglomerate, and the appearances seen on the lower slopes of 
the hills rising from below it in Prieska and Hope Town. We 
must first note that the conglomerate passes under the so-called 
Kimberley shales, or under the lowest sheets of dolerite at the 
bottom of the shales. The best localities for seeing this are at 
Uitdraai, about twelve miles east of Prieska Village, Groot Fourie’s 
Kolk, and Springbok Poortje, in the south of Prieska, and at many 
places in the north of Britstown. We have found no evidence in 
* “Ona Supposed Extensive Deposit of Coal,” &c. Cape Town, 1886. 
+ ‘The Glacial Origin of the Dwyka Conglomerate.” Trans. Geol. Soc. S.A. 
Johannesburg, iv., p. 103, 1898. 
