VICINITY of EDINBURGH. 423: 
ftate ; while it differed from No..37., the ftone on the fides, 
which were perfectly fimilar to each other in compofi- 
tion. 
Tracinc the friable purple-coloured portion upwards, I 
found it gradually became harder, and, of a fudden, chan ge to a. 
fine-grained blue-coloured greenftone ; and the part correfponde 
ing with the included mafs, alter to a hard coarfe-grained rock, 
(No. 38.) I foon obferved, that this coarfe-grained mafs, which. 
is about ten inches thick, continued. upwards, maintaining an 
uniform dimenfion and-pofition, in refpect to the walls of the. 
vein, as high as the eye could trace it in the rock, thus divid- 
ing it into two portions; that on the left fide being about eigh-- 
teen inches wide, while the other is about five feet. 
On. comparing the texture of the included ftripe, with that: 
of the walls on each fide, (No. 39. left fide; No. 40. included. 
ftripe; No. 41. right fide,) taken in a horizontal line, about fix. 
feet above the ftrata, I found as clofe a refemblance as it is poflible 
to conceive ; they are.all coarfe-grained, and highly cryftallifed. 
This fimilarity is not more remarkable, than the difference be-- 
tween the fubftance of the vein and the included mafs.. Speci-- 
mens taken from the junction of thefe, mark this in a ftriking. 
manner. No..42. is from the left fide of the right portion of 
the vein, to which the fine-grained part belongs. No..43. is 
from the middle of this portion; and No. 44. from the fide 
next the right wall.. Thefe were alfo taken in a: horizontal 
line, and exhibit the fame gradation of grain’ noticed as 
exifting in the great bed. Even in the narrow portion of. 
eighteen inches, on the left fide, this circumftance is quite vi- 
fible; but the fpecimens taken from the other are highly illu-. 
ftrative of the fac. 
Ji 
