TRANSACTIONS OF SECTION C. 995 
Macculloch strongly insisted that this great system of strata, which covers 
large areas in Sutherland and Ross, extending also into some of the Western Isles, 
is distinct alike from the Old- and the New-Red Sandstone; he asserted that it 
belongs to a far older period than either of those formations, and, employing the 
phraseology of the early geologists, he gave to it the name of the ‘ Primary Red 
Sandstone.’ ? 
Macculloch showed clearly that the strata of his ‘Primary Red Sandstone 
Formation’ are often found resting unconformably upon the gneissose and schistose 
rocks of the Highlands; but that in other places they appear to be overlain con- 
formably by, and even to alternate with, crystalline schists and gneisses. He was 
further able to state that the quartzites of his ‘ Primary Red Sandstone Formation’ 
contain organic remains, some of which he correctly identified as the burrows of 
marine worms, while others he recognised as Orthoceratites.* It is almost painful to 
have to add that his want of appreciation of the value of paleontological evidence, 
a wealmess which Macculloch shared with so many of the early Scottish geologists, 
prevented any attempt on his part at the correlation of this ‘Primary Red Sand- 
stone’ with the rocks of other districts; and thus for more than forty years this 
important discovery remained almost entirely fruitless. 
The next step in the history of our Inowledge of these Highland strata which 
we have to record, was unfortunately a retrograde one. Sedgwick and Murchison, 
who visited the district in 1827, maintained that Macculloch had fallen into 
grievous error, and that his ‘Primary Red Sandstone Formation’ was in fact no 
other than an outlying part of the Old Red Sandstone.* 
This view was strongly protested against by Hay Cunningham, who, writing in 
1839, after a careful survey of Sutherland, demonstrated the justice of Macculloch’s 
conclusions, and even went beyond that geologist in showing the very intimate 
connexion between the quartzite and limestone. He clearly illustrated by numerous 
sections the unconformity of the ‘Primary Red Sandstone Formation,’ consisting 
of red sandstone, quartzite, and limestone, upon the gneissose rocks, and the 
apparently conformable superposition to it of other schists and gneisses.* 
Such was the state of geological opinion when, in the winter of 1854, the 
attention of geologists was recalled to this ancient formation of Macculloch by the 
discovery in it of fossils by one who fully recognised their value and importance— 
Mr. Charles Peach. These fossils, though imperfect, were sufficient to prove that 
the strata containing them must be of Paleozoic age. 
Three of the leaders of geological science at that day appear to have been 
deeply impressed with the importance of this discovery of Mr. Peach’s; but for a 
time, at least, the fruits of that discovery were missed, through the unfortunate 
retrograde teachings of Sedgwick and Murchison in 1827. : 
Hugh Miller, whose splendid researches in the Old Red Sandstone had made 
him ready to welcome any extension of its boundaries, suggested that the fossils of 
Durness might belong to the marine Devonian. 
Roderick Murchison, who in his younger days had worthily conquered a king- 
dom in Siluria, and by successive annexations in his later years had sought to 
convert this kingdom into an empire—one which should embrace all the Lower 
Palzeozoic rocks of the globe—was not unwilling to claim his native Highlands as 
part of this ever-growing realm. 
James Nicol, who had been the first to discover graptolites in the rocks of the 
Scottish Borderland, and had thus demonstrated their Silurian age, was so struck 
by the resemblance of some of the slaty rocks of the Highlands to the fossiliferous 
shales of his native district, that, ten years before Peach made his important dis- 
covery, he had suggested the probability of the Highland schists and gneisses being 
’ Trans. Geol. Soc. ser. 1, vol. ii. p. 450, &e. Western Isles of Scotland (1819), 
vol. ii. p. 89, &e. System of Geology (1831). 
2 Western Isles of Scotland (1819), vol. ii. pp. 512, 513. 
3 Trans. Geol. Soc. ser. 2, vol. iii. p. 155. ; 
4 ¢On the Geognosy of Sutherlandshire,’ by R. J. H. Cunningham, M.W.S. ; Zrans- 
actions of the Highland and Agricultural Society of Scotland, vol. xiii. (1839). 
3s 2 
