532 H. HICKS ON THE PRE-CAMBRIAN 
supposed by the Director-General, the evidence is perfectly clear 
that the Cambrian strata are here faulted against the Dimetian, 
as shown on the plan. Of this there are abundant proofs of various 
kinds. The line of junction is most clearly marked, and the con- 
Fig. 5.—Plan of Allan Valley at Porth-clais. 
Mf ff, ceil Fe 
y: yyy, ]) Tadsercbed 
WN Wy Ml ~. ® 
// Bis 
WIL 
to St. Davids. 
i 
¥ 
to Porthlisky 
For explanation see fig. 3. 
Fig. 6.—Sketch in Allan Valley (south side) at Porth-clais, showing 
faulted contact of Cambrian Rocks with Dimetian. (The place 
specially referred to by Dr. Geikie as showing intrusion of the 
latter into the former.) 
2. Greenish sandstones. : A. Dimetian. 
1. Basal conglomerate. } Cambrian. F. Fault. 
glomerates can be removed without a particle of the true Dimetian 
being attached to them. There is no alteration set up in the 
