D. Balsillie — The Geology of Kinkell Ness. 499 



the southern shores of the Firth of Tay, in a contribution to 

 the Memoirs of the "Wernerian Society, 1 gave descriptions of the 

 remarkable "trap tuffs" in the neighbourhood of St. Andrews and 

 relegated them in characteristic Wernerian terminology to the newest 

 Floetz-trap formation, lief erring to the agglomerate and "spherical 

 concretion" of basalt at the Rock and Spindle he maintained that 

 the two rocks could be seen to pass insensibly into one another, and 

 accounted for the whole in the light of his adopted hypothesis by 

 inferring that it was " partly a mechanical and partly a chemical 

 deposit". 



From the time of Fleming for over the next sixty years little 

 appears to have been accomplished towards any correct elucidation 

 of the natural history of the tuffs in East Fife. They were mapped 

 by the officers of the Geological Survey as masses interbedded with 

 the rocks among which they occur, and this idea found expression on 

 the 1 inch map, sheet 41, published in 1861. Eighteen years later, 

 however, a change in concept was brought about by the appearance, 

 in 1879, of Sir A. Geikie's well-known paper "On the Carboniferous 

 Volcanic Rocks in the Basin of the Firth of Forth ; their Structure 

 in the Field and under the Microscope ". 2 In that paper the author, 

 turning to account, as he himself admits, valuable experience gained 

 on the East Lothian coast and in Ayrshire, clearly recognized 

 the intrusive nature of many of the tuffs, and asserted that these 

 represented the sites of former active volcanoes which must have 

 come into eruption long after the deposition of the Carboniferous 

 strata which they penetrate. More recently the same writer has 

 again given an account of them in his Ancient Volcanoes of Great 

 Britain, also, with amplification, in the Geological Survey memoir, 3 

 published in 1902. 



The general outline of the Rock and Spindle vent, as may quickly 

 be ascertained, is altogether irregular and suggests a shifting of the 

 focus of the volcanic forces by which it was produced. Thus two 

 nearly detached areas of agglomerate on the north may mark 

 independent orifices. Only on the eastern and northern sides are 

 the "margins of the opening available for examination, they being 

 concealed elsewhere beneath the grassy cliff-line and by the sand and 

 shingle above high-water mark. 



The rocks surrounding the neck, which consist in large part of 

 thinly-bedded sandstones with thick intervening shale bands, one of 

 which is crowded with Naiadites, lie not far above the Encrinite-bed, 

 which is an easily recognizable stratum in the Calciferous Sandstone 

 Series of East Fife, and which crops out on the beach about 300 yards 

 to the east of Kinkell Ness. On the Anstruther-St. Monans foreshore, 

 which is taken as the typical area for the study of the Calciferous 

 Sandstones in East Fife, Mr. Kirkby estimated the depth of the 

 Encrinite-bed beneath the base of the Carboniferous Limestone Series 

 as being about 2,280 feet. 4 On the north coast of the county, 



1 Vol. ii, 1813. 



2 Trans. Koy. Soc. Edin., vol. xxii, 1879. 



3 The Geology of Eastern Fife, Mem. Geob Survey, 1902. 



4 Q.J.G.S., vol. xxxvi, 1880. 



