On a Volcanic Series in the Malvern Hills, near the Herefordshire Beacon

Abstract

The rocks of the Malvern Hills have afforded scope for much study and discussion. Dr. Holl, Mr. Rutley, and Dr. Callaway have elaborated papers on them. Mr. Rutley's relates mainly to the general character of the rocks; while Dr. Callaway devotes himself to an enquiry into the genesis of the crystalline schists, and the production of secondary minerals in shear-zones. I propose to deal with a small area of the hills and describe some of the rocks to be found there. The district lies east and south-east of the Herefordshire Beacon, which has three spurs. The northernmost is Tinker's Hill, south of that comes Broad Down, and south of that again Hangman's Hill. The latter is, in its turn, bounded on the south by the ‘Silurian Pass,’ so named in the Geological Survey memoir by the late Prof. Phillips. The Beacon Hill itself is of the same character as the main axis of the hills. Prof. Phillips called attention to these rocks, and remarked that they ‘appear partly in lines like dykes.’ Dr. Holl also mentioned them, and considered them to be sandstone altered by the intrusion of trap-dykes. He noticed that some of the dykes contain a large proportion of augite. In a note to p. 100 ( op. cit. ) Dr. Holl says that fragments of these rocks are found in the Gullet Wood conglomerate. This statement requires investigation, as it might form a clue to the age of the series. Dr. Callaway has expressed the opinion that these rocks