ALTERED IIMESTONE OP STRATH, SKTE. 63 



ancient or so-called " primary " masses than of the Lias or any other 

 member of the Secondary series. "The interior," he remarked, 

 " presents a sceue of confusion that no ingenuity can develop ; in 

 which stratified and unstratified limestone, calcareous conglomerate, 

 quartz, sandstone and syenite occur in aj)parent defiance of all 

 reg-ularity " *. As the final result of his examination, he arrived at 

 the conclusion that notwithstanding the tumultuous disorder de- 

 scribed by him, the whole of the limestone must be referred to one 

 group which formed a part of the Secondary formations of the West 

 of Scotland. He reaffirmed the existence of a gradation from the 

 unstratified into the stratified limestone and of an alternation of the 

 one with the other, " which," to use his own words, " is highly 

 satisfactory, as tending to establish their perfectly consecutive 

 nature, and consequently to determine the place of the former lime- 

 stone without the shadow of a doubt "f* He accounted for the 

 striking contrast between difi'erent portions of the limestone by the 

 action of the eruptive igneous rocks. He had noticed several masses 

 of what was then termed " syenite " traversing the limestone in the 

 interior, and inferred that there might be others concealed beneath 

 superficial accumulations or existing below the surface, though not 

 actually reaching it. "It will be easily conjectured," he says, 

 " that I am inclined to attribute the whole of this confusion of 

 character or change of structure in the limestone deposit to the in- 

 fluence of the syenite " J. 



The conclusions thus announced were, of course, received with in- 

 credulity by the Wernerian geologists of the day. Ami Boue, who 

 occupied a curious intermediate position between the extreme Plu- 

 tonists and IJ^eptunists, expressed himself hesitatingly on the subject. 

 Bad weather had hindered him from visiting the sections in question 

 during his rambles in the Inner Hebrides ; but the possibility alluded 

 to by MaccuUoch had occurred to his mind also, that the so-called 

 " unstratified " limestone of Strath might quite well belong to the 

 transition period or at least to his series of " chloritic and quartzose 

 rocks " which he had found to cover so large an area of the High- 

 lands, and he saw how easily an error might be made if limestone 

 of 60 high an antiquity should here and there rise up in the midst 

 of similar younger stratified deposits. He could not understand 

 how such younger earthy and sandy limestones, even by the in- 

 tensest heat and pressure, could be changed into crystalline masses 

 containing silica, alumina, magnesia, and even transparent serpen- 

 tine. MaccuUoch's views were, he contended, opposed to known 

 analogies elsewhere and, on the other hand, were supported only by 

 that geologist's direct observations, which might possibly be erro- 

 neous, but which nobody was then in a position to controvert. 

 Hence, after balancing the contrary opinions, Boue impartially left 

 the question in doubt, but with the remark that the verdict might 

 ultimately be in Macculloch's favour §. 



* ' Western Islands/ vol. i. p. 322. t Op. cit. p. 328. 



X Op. cit. p. 332. § ' Essai geologique sur I'Ecosse,' pp. 207-211. 



