Reports & Proceedings—Edinburgh Geological Society. 235 
properties and chemical composition show that in this augite the 
diopside molecule predominates. 
Dr. G. T. Prior: “ On the Chemical Composition of the Adare 
and Ensisheim Meteorites.”” Determination of the amount and 
composition of the nickeliferous iron in these meteorites had shown 
that Adare contained 18 per cent in which Fe: Ni =11, and 
Ensisheim 3 in which Fe: Ni = 33. Analyses were made of the 
unattracted material in order to determine how far they supported 
the idea that in meteoric stones the ratio of MeO to FeO in the 
magnesium silicates varied directly with the ratio of Fe to Niin the 
nickel-iron. The results showed that the ratios of MgO to FeO in 
the olivine and pyroxene respectively were about 4 and 5 for Adare 
and 24 and 3 for Ensisheim. 
Mr. W. Barlow exhibited models to represent the atomic structure 
of calcite and aragonite. 
EDINBURGH GEOLOGICAL SOCIETY. 
February 16, 1921.—Mr. H. B. Bailey, M.C., B.A., F.G.8., F.R.S.E., 
President, in the chair. 
1. “ Recent Contributions to the Geology of Spitsbergen.” By 
Dr. Robert Campbell, F.G.S. 
After indicating the nature of the pioneer work done during the 
nineteenth century, Dr. Campbell outlined the results arrived at by 
Nathorst in his monograph on the geology of Bear Island, 
Spitsbergen, and King Karl’s Land, published in 1910. During the 
past decade notable advances, he said, had been made in our know- 
ledge of Spitsbergen geology, particularly by Hoel and Holtedahl. 
It had been known that the “‘ Archean ”’ of the north-west belonged 
to the Heclahook system. A strong case had been made, too, for 
regarding the Heclahook series as of Cambrian-Ordovician age, 
similar rocks in Bear Island having yielded a fauna of American 
facies resembling that found in the Durness limestones of North- 
western Scotland and in the Beekmantown limestone of North 
America. The Red Bay series of the North coast had yielded fossils 
suggestive of Downtonian age, and the remainder of the Devonian 
had been divided into three groups, comparable with the Caledonian, 
Orcadian, and Upper Old Red Sandstone of Scotland. They have 
yielded the same characteristic fishes, but, unlike their Scottish 
equivalents, they carried also, according to Holtedahl, several forms 
of marine lamellibranchs. The Carboniferous rocks were of interest 
because of the occurrence of coal seams in the Culm, and had been 
mapped in considerable detail by the geologists of various Norwegian, 
Swedish, and Scottish expeditions. Much new information of strati- 
graphical and paleontological value had been obtained. It had been 
established that great overthrusting movements had taken place— 
probably in Tertiary times—along the line of the fault that separated 
the Heclahook rocks of the west coast from the younger rocks to 
