23 



*" The most intense mechanical metamorphism occurs along the 

 grand dislocation (thrust) planes, where the gneisses and pegmatites 

 resting on those planes are crushed, dragged, and ground out into 

 a finely laminated schist or Mylonite (Gr. mylon a mill) composed 

 of shattered fragments of the original crystals of the rock set in a 

 cement of secondary quartz, the lamination being denned by 

 minute inosculating lines (fluxion lines) of kaolin or chloritic 

 material and secondary crystals of a micaceous mineral." 



f" The mylonites were formed along the thrust-planes, where 

 the two superposed rock systems moved over each other as solid 

 masses ; the augen-schists were probably formed in the more central 

 parts of the moving system, where the all-surrounding weight and 

 pressure forced the rock to yield somewhat like a plastic body." 



The Geological Survey was close on Lapworth's track. Armed 

 in 1883 with six-inch maps, half a dozen of their most competent 

 Surveyors soon came into contact with the inexorable facts on 

 which Lapworth's deductions were founded. In a report printed 

 in Nature in November, 1884,! illustrated and considerably amplified 

 on communication to the Geological Society in 1888, they not only 

 confirmed the work that Lapworth had published, but in some 

 instances advanced beyond anything he had published. Later 

 still, in 1907, appeared the great Survey Memoir on the North-west 

 of Scotland. 



It was after the appearance of the report in Nature that 

 Lapworth published a short note (33) entitled ' On the Close of the 

 Highland Controversy/ in which he summed up the history and 

 present position of the work in that region in a generous spirit 

 and in masterly fashion. In this he states J" the conclusions 

 at which I arrived seem to me to be identical in all their essentials 

 with those recently published by Messrs. Peach and Home " ; 

 and again, referring to his " own results in so far as they affect 

 the age, composition, and mode of formation of the eastern 

 schists," *" The officers of the Survey reached their conclusions 

 in complete ignorance of my results, and from a totally different 

 direction." A mind not so great might conceivably have been 

 tempted to express or feel it a hardship that he had not been given 

 the opportunity of finishing his own work in his own way. Instead, 

 he welcomes this complete confirmation and vindication of his 

 work, warmly congratulates his rivals on their success, and turns 

 to other matters. I should like to quote, for the white light it throws 

 on the character of the man, the whole of his closing paragraphs, 

 but I limit myself to one of them. " At the present time the 

 several groups of students of these old rocks are all met together 



* 35, p. 1026. 



j- Nature, vol. xxxi, 1884-5, pp. 29-35, Quart. Journ. Geol. Soc., vol. xliv. 

 (1888), pp 378 441. ~ t 33, P- 98. 33. P- 102. 



