3r-32° 



E 



48°-49'' 



E 



7°-8° 



E 



4°-6° 



E. 



5°-6° 



E 



36^-36° 



E 



O'Reilly — On Jointing in Rocks about Dublin, ^c. 119 



Malahide Strand — continued. 



317 15 yards east of this, a set of joints, sparry, and one of 



them IJ in. thick, 



318 Thin joints near these, 



319 Others, .... 



320 Sparry and thick joint, 



321 Set of five joints, 



322 Crossed hy others at, 



323 150 to 180 yards south-east of old castle, sparry joint, 



vertical, 1|- in. thick, very distinct, .... 2°-3° E. 



324 Set of spar and Dolomite joints, 1, 1|, and 2 in. thick 



at intervals of about 2 ft., . . . .'' . 7°-8° E. 



325 Set of four sparry joints, 2 to 4 in. thick, well marked, 14° E. 



326 "Well-marked sparry but wabbling joint, . . . 42° E. 



327 Set of sparless joints, well-marked, nearlv perpendicular 



to beds, ■ . . . 5°-6° E. 



328 "Well-marked sparless joint, ...... 8° E. 



329 Cross jointing of beds, 12°-13° E. 



Beds of Dolomite coming on here, direction N""' 92° 

 east, dip to north at 26°, running towards east 

 point of Lambay Is., finely jointed by joints at . 32° E. 



330 Close sparry jointing, crossing Dolomite, and apparently 



anterior to tilting of beds, ..... 23°-24° E. 



331 Jointing with Dolomite lining, and evidently having 



caused dolomitization of beds where traversing, . 3°-4° W. 



332 Thick beds of Dolomite here, from which road metal 



being obtained. Dip towards north at 41°. 



333 Thick 8 in. vertical Dolomite joint, traversing same 



beds, 8° E. 



334 Joint in the Dolomite here, ..... 27°-28° E. 



335 Portion of a thick, vertical. Dolomite joint, . . . 24°-25° E. 



Anticlinal at this point, / N"^- 61° E. ] -.j 

 apparent direction of < ,, 63°-64° E. / (-10 on» 

 axis, . . • ( ,) 60° E. ) 



336 Dolomite dyke or horse, bounded on the south side, ver- 



tical ; the Dolomite highly crystalline, and cleaved 

 into small Rhombohedrons, ..... 53°-54° E. 

 Direction of beds of Dolomite on east side of great 

 axis N"- 30° E. ; dip 19° towards S.E. 



337 Very close, irregularly, branched, and well-marked 



Dolomite jointing, in connexion with great main 



joint, 22°-23° E. 



338 Direction of limestone beds about 50 yards south of 



great joint, N"^- 82°-83° E. 



Dip to south at . . . . . ,, 25° 



339 Traversed by jointing, sparry and " gashed," . . 23°-24° E. 



340 Jointing in contorted limestone beds under sustaining 



wall of road, 19° W. 



Synclinal trough here. 



