119 
NOTE ON 
THE METAMORPHOSED SKIDDAW SLATES. 
(TRANSLATED FROM PROF. H. ROSENBUSCH.] 
[THE following is extracted from Professor Rosenbusch’s work Die 
Steiger Schiefer, pp. 211-213 (1877). Occurring in a memoir of the 
Geological Survey of Alsace-Lorraine, it will be new to many readers, 
and as it contains important corrections and additions to the well- 
known work of the late Mr. Clifton Ward, it may be worth 
reproducing here.—A.H 
J. Clifton Ward* recently made some extremely interesting 
communications on the contact-zones of the clay-slates around the 
granites in northern England, the so-called Lake District. Through 
the kindness of my friend Lossent I was enabled to study specimens 
of the three stages of metamorphism distinguished by Ward, from 
without inwards; viz. Chiastolite-slate, Spotted Schist, and Mica-schist. 
A piece of chiastolite-slate from the slope of Skiddaw opposite 
Landscale showed a normal clay-slate with porphyritically imbedded 
chiastolite crystals, in no way differing from the known occurrences 
of the Fichtelgebirge, Brittany, and the Pyrenees, and thoroughly 
agreeing with the occurrence in the Erlen valley in the outermost 
zone of the contact-ring of the Barr-Andlau granitite. Of crystalline 
new-formation there is nothing else to be seen in it except a few 
laths of a colourless mica and little chlorite-scales. The great 
abundance of carbonaceous matter allows nothing more to be 
Tecognized than the quartz-granules and the above-named minerals, 
with yellow doubly-refracting grains of indeterminable nature. The 
chiastolites are comparatively pure, but still only seldom so fresh that 
On€ can perceive the characteristic pleochroism. . 
The stage of anid seg next following the Chiastolite-slate 
was designated by Ward ‘Spotted Schist’ (Knotenschiefer): the 
description which Ward gives of it agrees only very badly with the 
occurrence which I have been able to study. This comes from the 
slope of Skiddaw opposite Landscale. The spots stand out very 
little, in a thin slice, from the rest of the rock: they consist of just 
the same minerals as form the slate, and owe their origin only to 
a me slight accumulation of carbonaceous matter: they 
he Granitic, Granitoid, and Associated Metamorphic Rocks of the Lake 
ist) Seidl: Journ. Geol. Soc. (1875) xxxi, pp. 568-602 ; (1876) xxxii, pp. 1-34. 
n has elsewhere compared the Skiddaw metamorphism with that on the 
north side of the Ramberg granite in the Harz; Zeits. deuts. geol. Ges. (1872), 
Xxiv, p. Pp. 716.) 
April 186 1892. 
