410 C. CALLAWAY ON THE NEWER GNEISSIC 



IV. Summary of Results. 



1 . The Assynt series has been doubled back upon itself in a com- 

 pressed synclinal fold along Loch Emboli, so that the Quartzite is 

 brought up over the Dolomite. In Assynt, also, the quartzo-dolomitic 

 group has been folded back, though less conspicuously. On Loch 

 Broom, the Dolomite does not come into contact with the Eastern 

 Gneiss at all, but is separated from it by older faulted rocks. 



2. The Assynt series and the Eastern Gneiss in the three areas 

 described display a discordant strike and dip. On Loch Broom the 

 dip of the former is north-easterly, that of the latter south-easterly. 

 In Assynt, where the rocks are in contact, as at Glen Coul, the dip 

 of the gneiss is north-easterly, that of the quartzite south-easterly. 

 On Loch Emboli* the discordance is double, both the gneiss and 

 quartzite, taking them from north to south, coming respectively into 

 contact with higher and higher beds of the other group. 



3. The " Igneous Bock " of some authors, " Logan Bock " of Dr. 

 Heddle, is usually the Hebridean gneiss. On Loch Broom it is 

 brought into contact with almost every member of the Assynt series 

 in turn, and slightly overlies them. In Assynt this gneiss, some- 

 times accompanied by the Torridon Sandstone, is thrown over onto 

 the Assynt series, the overthrow increasing in breadth northwards, 

 so that on Loch Glen Coul it is more than a mile wide. The " in- 

 trusive granulite" of Nicol is the Arnaboll gneiss overlying the 

 Quartzite and associated rock. 



4. The determination of the last point materially adds to my 

 argument, the patches of quartzite resting on the " granulite " being 

 really outliers of the Assynt series lying unconformably on the 

 Arnaboll gneiss. The absence of granite veins in the Assynt series 

 points in the same direction. 



5. The " Upper Quartzite " of authors is, in Assynt, the quartzite 

 under the dolomite repeated east of the fault, which brings up the 

 Hebridean. On Loch Erriboll it is the same quartzite repeated on 

 the eastern side of the great synclinal fold. 



6. The " Upper Limestone " is, on Loch Ailsh, marble and crys- 

 talline dolomite in the Caledonian series. Near the Stack of Glen 

 Coul it is the Assynt dolomite repeated east of the Hebridean fault. 

 Above Erriboll House it is a faulted fragment of the dolomite ap- 

 pearing east of the inverted quartzite. ' 



7. The Eastern Gneiss, though actually overlying the Assynt 

 series in some localities, has been brought into this abnormal posi- 

 tion by earth-movements subsequent to the deposition of the latter, 

 and is of greater antiquity. 



8. The Eastern Gneiss is widely separated in age from the 

 Hebridean. 



* If the Arnaboll series should, contrary to my belief, turn out to be the older 

 gneiss, my case would be even strengthened ; for then we should have the 

 Quartzite along the same line resting against both Hebridean and Caledonian, 

 and, according to the old vieWj -passing conformably beneath both. 



