18 



of more receni deposits, llie total tliickness of wiiicli aiiioniits, for 

 the paleozoic only, to over 12.000 iii. in the Apallaehiaii. 



Here then we have an instance of well developed, siniilarl)- coii- 

 stitnted sediments, deposited over vast areas, diftering considerably 

 in age and covered nnder layers of sediments, whoso thickness 

 amounts to 2000 m. and 12.000 ni. and more. 



Yet their pore-space was and is, very nearly identic, ami ntorc- 

 ovc-i' coincides icitli that of similiir si'iHineiits ir/iic// hotlt nrc n'cciit 

 oikJ situated close to the surface. (5). 



On the gronnd of these facts, the conclusion does not seem un- 

 warranted, that the pore space now proved to exist in these sand- 

 stones, was also present in them when they were still lying in the 

 G.S. covered up by a powerfnl mass of more than 2000 m. ami 

 12000 m. thickness. 



It would not be diflicnlt to ijicrease tiie instances given above. 



If it seems legitimate, on the gronnd of the above detailed facts 

 to conclude that pore space in sedimentary rocks is existable at 

 depths of more than 12.000 ni., the recently published results of 

 F. D. Adams's researches and L. F. King's calculations proved that 

 we may yet expect them to exist at far greater depths, even when 

 those pore spaces mere not filled up bij some liquid or (/as iui prisoned 

 in- thru). 



Were these pore spaces filled with a liqnid or gas, we might 

 expect them to be still extant at depths where the temperature is 

 so high, that nnder its influence the sediments wonld liquefy. 



The question is now whether we may take it as probable, that 

 the water originally occluded in these sedimentary deposits, will 

 not have been expelled from there (by the tension of the vapour- 

 converted water of underlying strata), long before those sediments 

 could have reached the zone of liqnefaction. 



B'or should the water (vaponr) still fUl the pore-spaces, a snfticiently 

 sound basis for explaining the origin and mechanism of volcanism 

 were to be found, in the quantity of occluded water (vaponr) and 

 the high tensions acquired by it, nnder the intlnence of excessive 

 high temperatnres reigning in the magmatic zone. 



The sedimentary rock would gradnally pass into a plastic and 

 liquid condition, during its downward course in the G. >S. 



And as the steep Hank of the (1. A. adjacent to the G. S. constitnte 

 a faulted and fissured region, the possibility might not be considered 

 excluded that part of those vapour-tensions will discharge themselves 

 iiUo those fissures, thus creating the volcanic phenomenon at the 

 snrface of the earth. 



