Correspondence. 317 
and may even have consisted of larger pebbles of gneiss or granite. 
The granulite is also clearly stratified and presumably a metamorphic 
rock. These facts and opinions recall those presented by Dr. Edward 
Hitchcock in the Geology of Vermont, and those at Obermittweida in 
Saxony, and the conglomerates in similar situations in Canada.^ Dr. 
Reusch is also clearly of the opinion that the pebbles of the conglom- 
erates have been flattened, and in many cases stretched or elongated 
after being softened by igneo-aqueous action. The partially folded 
lenses of the green gneiss of Trengereid he regards as a pressed breccia. 
A brecciated condition, as he suggests, sometimes results from the 
presence of a multitude of thin intersecting veins ; and the anomalous 
occurrence of a plicated bed between two unplicated l)eds he explains 
ingeniously by the slipping of one of the unplicated ones over the 
other, with an intervening bed which wrinkles instead of slipping 
bodily. 
These gneissio and schistic rocks of Upper Silurian age or later, 
derived from indisputable sedimentary terranes, indicate, like other 
similar facts long known, the possibility— perhaps the probability— of 
a similar origin for the similar rocks occurring in sub-Cambrian zones. 
Bommeliien og Karmoen med omgivelser geologisk heskrevne af Dr. Hans 
Reusch. With 3 colored charts, 205 cuts in the text and an Englisli 
summary of the contents. Udgivet af den geologiske underscigelske. 
Royal 8 vo. pp. 442, Kristiania, 1888. ^ 
This elegantly printed volume contains a continuation of Dr. 
Reusch's careful investigations of the geology of Norway. It pos- 
sesses interest, like his former memoir (noticed above) for American 
geologists, because much of the geology of Norway, as Macfarlane long 
ago pointeil out, is the counterpart of the Arehrean geology of Canada 
and the United States, and because the principles elucidated by Nor- 
wegian geology possess direct and fruitful ai)plioation in the solution 
of problems in American geology. 
The regions described in this volume extend from Bergen southward 
to Stavanger, including the borders of the Hardanger, Bommel an<l 
Bokne fiords ; but more particularly the environs of B()mmelo and 
Karmo. The rocks appear to be chiefly of Archiean, Primordial and 
Silurian age. Petrographically they are gneiss and granite, mostly 
Archaean, associated with crystalline schists, chiefly clay-slates and in 
places containing Primordial fossils. The fossils are sometimes in 
limestones embraced in the .slates. Angular fragments, large and 
small, occur in the gneisses and granites, and the former, in numerous 
localities described, hold ellipsoidal, bowlder-like foreign fragments, 
disposed in courses, which are frequently accumulated to such extent 
as to result in proper conglomerates. In the forms of the fossils and 
pebbles the author sees remarkable evidences of compression and 
'■'On the relation of conglomerates to gneisses and crystalline schists, 
see the articles by A. Winchell in Tnv. American Geologist, March 
and April, 1889, wlune references may ])e found. 
'See a review of this work in this journal, vol. m. p. 335. 
