CHAP. XL VII 
THE LATEST DYKES OF ST. KILDA 
417 
bands. They consist of basalt-rocks, and may often be seen to branch and to 
die out. Like those in the gabbro, they are not infrequently compound, 
Fig. 367. Section of the sea-cliff below Conaoher, St. Kilda, showing basic dykes in granophyre. 
being made up of two or three or even more distinct dykes. This is well 
seen ^on the great precipice below Conacher, where the section given in 
fig. 367 is displayed. Here in a vertical height of about 800 or 900 feet, 
there must be at least seven dykes, simple and compound. A little further 
south a triple dyke may be seen to be composed of a thick central zone 
and two thinner marginal bands, of which the lower strikes off from 
the others and maintains an independent course through the granonhvre 
(Fig. 368). G v * 
