62 THE OLDEST ROOKS OF ENGLAND. CHAP. 



THE FIRST OR GNEISS PERIOD OF MALVERN 



is marked by the appearance of laminated deposits, in which mica 

 or hornblende, or both, occur with felspar and quartz. The laminae 

 are very distinct and flexuous about Malvern Wells, on the eastern 

 side of the ridge. Hocks of the same system about the Wych are 

 less distinctly formed of granular minerals ; others allied to them 

 in the North Hill are, on the contrary, granitic in their aspect. 

 Containing, as they do, hornblende very generally as an ingredient, 

 most of these rocks of the North Hill were termed syenite by Mr. 

 Leonard Homer, Sir R/. Murchison, and myself; but the latest 

 observer, Dr. Holl, regards them as of the same metamorphic 

 origin as the unquestionably gneissic strata of Malvern Wells, and 

 compares them in point of date with the very old gneiss of Canada 

 the Laurentian series, in which eozoon occurs the earliest known 

 or supposed form of life. 



Traversing these rocks in veins, or somewhat irregularly dispersed 

 in masses among them, are very largely crystallized mixtures of 

 quartz and orthoclase felspar, quartz and mica, felspar and mica, or 

 quartz, felspar, and mica, with or without hornblende. Such may 

 be seen on the ridge above Great Malvern, in the road to the Wych, 

 where also occur bands of silvery or golden mica, greenish horn- 

 blende, and a kind of grey talc. Epidote is a frequent mineral 

 in the gneissic and syenitic bands over North Malvern and West 

 Malvern. Another beautiful variety of rock is formed by the 

 mixture of rich broad-plated hornblende and a felspar of white 

 or pale reddish tint, not distinctly crystallized, certainly not 

 orthoclase, and probably less rich in silica. To this rock the name 

 of ' diorite j may be given, according to the nomenclature of Cotta. 

 It has usually been placed in one of the vague groups of syenite 

 or greenstone. 



Segregation from a fused mass is often regarded as the 

 cause of these irregular mixtures; in several cases, however, the 

 posteriority of felspathic and granitic veins to the masses which 

 they traverse is quite certain, but they are of earlier date than 

 any of the Silurian strata. 



The old gneissic, felspathic, and hornblendic rocks of Malvern 

 are variously jointed and fissured; in some cases the divisional 



