350 Professor T. Rupert Jones — The Enon Conglomerate 



rivers ; we have 105 millions of years if the correction should be 

 33 per cent. I do not believe an unbiassed consideration of the 

 knowledge at our disposal will permit of an allowance larger than 

 the latter. 



I have given the foregoing estimation in its algebraic form in 

 consequence of the remark of a writer in Nature (in a review of my 

 paper) that it was a pity that the age of the Earth has to be assumed 

 in making allowance for the primeval acid denudation. Such 

 assumption of the duration we seek to determine is not, however, 

 necessary, as the foregoing algebraic statement shows. 



The teaching of the calculation which I gave in my original 

 paper, that the missing sodium of the rocks is equal to or in excess 

 of that added to the ocean during geological time, has been taken by 

 some as by no means opposed to the view that the ocean may have 

 primevally contained the greater part of its present sodium, or to 

 a rapid convergence in the rate of solvent denudation. 



The greater part of these sediments, we are assured, were laid 

 down under conditions not even inimical to life, or, as Sir Archibald 

 Geikie has contended for the very ancient Torridonian rocks, under 

 physical conditions much as obtain to-day. But this is not all. 

 The oldest sediments are just those which are chemically the least 

 impoverished and the least washed out of the whole series, and, 

 indeed, might almost be identified by their higher alkali percentages. 

 This fact is obviously quite opposed to the view that they were 

 exposed to more intense solvent actions than obtain to-day. In 

 a word, the internal evidence, chemical, physical, and oi'ganic, 

 afforded by the successive strata, controverts the convergence of 

 denudative activity which some have casually assumed, and in 

 the light of this fact the calculation in question does oppose the 

 theory of a sodium-charged primeval ocean. We are assured, in 

 fact, that the introduction of sodium age by age had to wait upon 

 the denudation of the rocks, and was thus regulated by a rate to 

 which we know of no disturbance. 



III. — On the Enon Conglomerate of the Cape of Good Hope, 

 AND ITS Fossil Estheri^. 



By Professor T. Eupert Jones, F.E.S., F.G.S., etc. 



IN the " Annual Eeport of the Geological Commission " published 

 at Cape Town in 1895, Dr. Corstorphine refers at pp. 16-19 

 to the extent and features of the Enon Conglomerate, and to the 

 occurrence of fossil Estherice in some of its strata. His two assistant 

 geologists, Messrs. A. W. Kogers and E. H. L. Schwartz, in their 

 " Eeports on the Southern Districts between Breede Eiver and 

 George " and " On Oudtshoorn," at pp. 73, 76-79, describe in detail 

 the position and characters of the Enon Conglomerate and its 

 ' Esiheria shale.' 



This Conglomerate (with its sandstones and shaly beds) occurs in 

 the Breede River valley, Worcester Division of the Western Province, 



