392 The Nicol Memorial. 



transferred tlie sphere of his geological investigations to the 

 metamorphic rocks of the Highlands, which in 1844 he had suggested 

 were probably of the same geological age as those of the Southern 

 Uplands. In 1855 he published his paper " On the Sections of 

 Metamorphic and Devonian Eocks of the Eastern Extremity of the 

 Grampians " (Quart. Journ. Geol. Soc, vol. xi, p 544). 



The same year he visited the well-known Torridon and Durness 

 area in the North- West Highlands in company with Sir R. Murchison, 

 in order to verify Mr. Peach's discovery of fossils in the metamorphic 

 limestone of that region. On his return he communicated an 

 independent memoir to the Geological Society (Quart. Journ. Geol. 

 Soc, vol. xiii, p. 17), in which he claims to have published for the 

 first time their order of succession, viz. : (a) Lower Gneiss ; (6) 

 Conglomerate and Red Sandstone ; (c) Quartzite ; {d) Limestone, 

 overlain by (e) an Upper Gneiss. Arguing mainly from the petro- 

 graphical character of these rocks, he threw ou^ the suggestion 

 that the Torridon Sandstone might be of Devonian age, and that the 

 overlying limestone and gneiss might be of the age of the Lower 

 Carboniferous. After Mr. Salter's demonstration that the fossils 

 of the Durness Limestone were not Carboniferous, but belonging 

 to the deepest zone of Murchison's Silurian, Nicol again visited the 

 North- West Highlands. In a memoir giving the chief results of this 

 expedition (Quart. Journ. Geol. Soc, xvii, p. 85) he retraced his 

 former admission of an Upper Gneiss, superior to the Durness 

 Limestone ; and claimed to have proved that the line of demarca- 

 tion between the Durness series and the eastern gneiss of Central 

 Sutherlandshire is actually a line of fault, the Torridon and Durness 

 strata always overlying or abutting against, but never dipping under, 

 the eastern gneiss. These opinions led to a keen controversy between 

 himself and his old friend Sir R. Murchison ; but after the publication 

 of two additional memoirs on the subject in 1862 and 1863, in 

 which he defended his view that the central gneiss of the Highlands 

 is of the same general geological age as the Lewisian gneiss of the 

 Outer Hebrides, and that the only metamorphic strata that can 

 safely be called " Silurian " are the less altered rocks upon the outer 

 borders of the Highlands, he ceased to contribute papers to the 

 Society upon the subject. A little work. On the Geology and 

 Scenery of the North of Scotland^ contains his last published 

 words upon the subject. 



* * * * * # * 



" The Close of the Highland Controversy," written by Professor 

 Lapworth (see Geol. Mag., 1885, pp. 97-106), and the admirable but 

 brief address by Dr. John Home {ante, pp. 388-90), furnish a suitable 

 note to Professor Nicol's life and researches, most of the friends and 

 contemporary actors in which have now, like himself, " ceased 

 from their labours." But the value of their conclusions have 

 left a permanent impress for good on the modern school of 

 geological thought and science which can never be forgotten. — H.W. 



