256 



PEOCEEDINGS OF THE GEOLOGICAL SOCIETY, [Apr. 16, 



are used for building-purposes at Callander, have a S.E. dip at a 

 high angle. Their relation to the strata dipping N."W., as seen 

 between the Bridge of Allan and Lanrick, is not apparent in the 

 district drained by the Teith ; but in the course of the Keltic, which 

 joins the Teith from the N., the connexion of the conglomerates of 

 Callander with the rocks on the S.E. can be well made out. 



In the course of the Keltic, about half a mile above the bridge, on 

 the road on the north side of the Teith leading from Callander to 

 Doune, at the Mill Weir, the grey sandstones above referred to are 

 seen ; and here they have a horizontal position. On ascending the 

 stream the same strata occur, and become more highly inclined ; 

 beneath these upper grey sandstones there are seen brownish-red 

 flaggy strata, conforming to the higher series in dip. The brownish- 

 red flagstones gradually increase in dip to Bracklin Linns, where they 

 become coarser ; and some of the beds, in consequence of containing 

 quartz -fragments, put on the aspect of a fine conglomerate. Some of 

 the surfaces of the beds at Bracklin Linns exhibit weU-marked 

 ripples, and here the strata dip S.E. at 75°. 



Above Bracklin Linns in the course of the Keltic these conglome- 

 rates and associated red sandstones also occur, the former prevailing 

 to a greater extent than the sandstone layers ; but these beds pass 

 downwards into thin-bedded brown flags, which rest upon a series of 

 fine-bedded, light-purple, micaceous sandstones. Eine conglomerates, 

 with quartz -pebbles, are seen below the purple micaceous sandstones ; 

 and under these latter are reddish- coloured shaly sandstones, reposing 

 upon sandstones of a grey coloui', and bearing great affinity to the 

 grey sandstones of the Bridge of AUan. 



Diagram-section from the Bridge of Allan to Callander. 

 Distance 12 miles. 



W.KW. E.S.E. 



DoTine The Bridge 



Callander. Bracklin Linns. Lanrick. Castle. Craig Amhall. of Allan. 



\ 



12 3a 



8. Carboniferous rocks. 



7 & 6. Brown sandstone surmount- 

 ed by grey sandstone. 



5. Purple shale. 



4. Grey sandstone passing upwards 

 into red sandstone. 



* Place where remains of Pteraspzs 



Fault. 



and Ce;p7iala&pis have been 



found. 

 Zh. Trappean conglomerate. 

 Za. Conglomerate of felstone. 

 2, Trap-rock. 

 1. Metamorphic Lower Silurian 



rocks. 



These latter are weU seen in the lower portion of a beautiful Linn 

 in the course of the Keltic, about a mile above Bracklin Linns ; and 

 here they rest upon brown sandstones with well- developed con- 



