300 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



Indian peninsula with Africa. (Compare with this the liecord 

 for 1877, p. 179). 



The Carboniferous strata already noticed are followed by 

 a great series of Triassic, Liassic, and Cretaceous strata, the 

 whole succession down to the base of the Cambrian salt- 

 group being here apparently conformable. In some regions 

 farther northward the rocks are very much disturbed and 

 even completely inverted, as in one case where, in the ab- 

 sence of the Cretaceous, Jurassic beds are found resting for a 

 considerable distance at low angles on the Eocene Tertiary. 

 In another locality the Trias itself appears overlaid by crys- 

 talline schists. Phenomena of inversion on a great scale are 

 common in the Himalaya region. In Afghanistan, along nu- 

 merous parallel ridges, the reversed anticlinals present exam- 

 ples of completely overturned strata, lying nearly horizontal- 

 ly over the same beds in their normal position for breadths 

 of from a quarter to nearly half a mile. The salt deposits at 

 the base of the Tertiary are very local ; but the great mass 

 of Tertiary strata, including the Siwalik sandstones and con- 

 glomerates, with their remarkable vertebrate fauna, are wide- 

 ly spread, and of immense volume, having, at a reduced esti- 

 mate, a thickness of not less than four or live miles. Above 

 all these are deposits of Post-tertiary gravels and silt, over 

 and upon which are numbers of erratic blocks along the left 

 bank of the Indus. These, unlike the rocks in the older con- 

 glomerates, appear to have a Himalayan origin, and their 

 transportation is variously assigned to floods, to floating ice, 

 and to terrestrial glaciers. 



GEOLOGY OF THE ARCTIC REGIONS. 



Among the geological results of the polar expedition un- 

 der Sir George Nares, it may be noted that the ancient crys- 

 talline rocks (called, by Fielden and De Ranee, Laurentian 

 gneiss), outcrops of which are widely spread in the polar 

 area, are directly overlaid by Cretaceous and Tertiary on Dis- 

 co Island, by Jurassic on the east coast of Greenland, and by 

 Paleozoic rocks in the Parry Archipelago ; while on the coast- 

 line between Scoresby ]>ay and Cape Creswell unfossiliferous 

 shales and grits of unknown age rest at high angles upon 

 the gneiss. The Paleozoic strata include a large develop- 

 ment of Carboniferous limestone, well-characterized marine 



