ANXIVERSAEY ADDRESS OF THE rKESIDENT. 1 57 



that the vents were active only in the early part of the period repre- 

 sented by the red sandstones, for it is entirely in the lower part of 

 these strata that the volcanic rocks occur. The eruptions gradually 

 ceased, and the sheets of ejected material, probably also the volcanic 

 cones, were buried under a considerable thickness of red sandstone. 

 Whether or not any portion of the erupted material was built up 

 above the level of the water, there seems to be no question that the 

 vents were, on the whole, subaqueous. 



From the Ayrshire plain a few widely scattered vents, which may 

 belong to the Permian series, may be traced across Lanarkshire and 

 Midlothian to the Firth of Forth.^ But it is in the east of Fife that 

 we next meet with a large assemblage of them. ]^o trace of any 

 sandstones which can be even surmised to be Permian has there 

 been detected; hence the geological age of the vents now to be 

 described can only be inferred from the kind of indirect evidence 

 already alluded to. But the inference appears to be well grounded, 

 for it is based on the fact that some of these necks, like those of 

 Ayrshire, pierce the highest group of the Coal Measures. In these 

 instances, therefore, it can be shown that the eruptions took place 

 after the Coal Measures, and the only known post-Carboniferous 

 volcanic period to which they can be referred is that with which we 

 are now dealing. But the necks which happen to rise through the 

 Coal Measures are only part of a large group that rises indifferently 

 through the Carboniferous Limestone series and Calciferous Sand- 

 stones of the east of Fife. They are assuredly all one connected 

 aggregate, resembling each other alike in their external characters, 

 internal structure, and component materials, and the limit of their 

 age must be determined by the geological horizon of the youngest 

 formation which they traverse. By this process of reasoning I reach 

 the conclusion that this remarkable series of old volcanoes in the 

 east of Scotland dates from the same jjeriod as that of Ayrshire and 

 Nithsdale. 



Some idea of the importance and interest of the volcanic area of 

 eastern Fife may be gathered from the fact that in a space of about 

 70 square miles no fewer than 60 necks may be counted, and others 

 are probably concealed under Carboniferous strata and below the 

 drift-deposits which cover so much of that part of the country. The 

 area extends from St. Andrew's Bay and the Yale of the Eden south- 

 wards to the coast of the Firth of Forth from Luudin Links to St. 



^ I have little doubt that the later rocks of Arthur Seat, which can be shown 

 to pierce the older bedded masses, belong to this series. 



