THE ROCKS OF PATTERDALE (ULLSWATER). 
P. Q. KEEGAN, LL.D. 
REGARDING Patterdale as extending from Stybarrow Crag and 
grouped under the eruptive rocks of the Borrowdale series, and 
are supposed to be of lower Silurian age. The State geologists 
represent them on their map, sheet tor S.E. (new series, sheet 
29), as being composed for the most part of volcanic ash, with, 
however, several well-marked and distinctive sheets and bands 
traversing the valley, are almost’ entirely of volcanic ash, and 
the sky-line summits of the mountains are likewise of the same 
material, except in a few places, such as Annstone Crag and 
portions of the summit of Place Fell, where the dark and jagged 
outline betokens the presence of lava. A general review of the 
present condition of these rocks reveals the fact or supports the 
supposition that either the rocks forming the hills on the western 
side have resisted decay and disintegration more successfully 
than those on the eastern side, or else that they actually have in 
the past been considerably abraded and destroyed, and are now 
in a position of comparative stability. 
of a series of rocks comprised in a mountain valley may be 
take as many sections as possible. This, of course, would 
be saved and so far compensated for by securing a small series 
of sections at certain definite and suitably-selected spots. Thus, 
for instance, where a series of mountain arms or upland reaches 
push forward together and constitute, with intervening valleys, 
the western flanks of Patterdale, a rock-section from the 
extremity of each arm may suffice to convey a_ tolerably 
adequate idea of the nature and constitution of the rocks on 
that side of the field of investigation. And, on the other hand, 
Obviously, in order that a complete and gdeguats description | 
supplied, it would be necessary to survey the entire field, and to 
involve herculean labour and much time, which may, however, | 
_ where, as on the eastern side thereof, the hill screens, save for the ae 
shallow gaps of Boredale Hause and Angle Tarn ey present 4 an aS ie 
unbroken sas for a phe stretch, a serie 
