485 
Dr. Berger's Account of the Isle of Man . 
Dr. Berger mentions the composition of this granite only at the 
spot where it occurs in a decomposed state ; but at greater elevations 
it is perfectly compact, the quartz and mica bearing as large a 
proportion to the felspar as usual. The mica is black and the 
varieties of texture numerous, but it is impossible to trace with any 
degree of certainty the beds which constitute the different changes, 
as no very extensive section is formed in the rock. All that can 
be stated is, that the greater the elevation, the more compact and less 
decomposed the aspect ; and on approaching the stratified rocks to 
the south, the mica gradually yields to chlorite, the quartz at the 
same time becoming less abundant, till some varieties are little else 
than felspar and chlorite. 
If I have been prolix in my directions for detecting the locality 
of the granite here* it has arisen from the desire of leading future 
geologists to the spot without that loss of time which might 
otherwise attend their search. For it is situate between two streams 
not half a mile distant from each other, whose courses any inquirer 
would naturally be led to explore. On finding the dip and direction 
of the stratified rocks which form the bed of each to be the same, he 
would most probably conclude that they were parts of a continuous 
bed, and thus overlook the granite which occupies the intermediate 
space : a circumstance, which not only happened to myself upon 
first visiting the spot, but even, as I was informed, to a celebrated 
geologist, who was there the previous year.. 
The above is the only spot where Dr. Berger mentions having 
met with granite in situ ; but another more extensive tract of this 
nature occurs to the south of Foxdale. The main body forms a hill; 
or ridge, stretching nearly north and south for about one mile, and is 
called by the inhabitants a Slieu-ny-clough,”or “the Stony Mountain.” 
The best section of this is formed by the course of the river which 
