Beschreibung:
Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The granitic gneisses of Erris (north Mayo), of the Ox Mountains, Connemara, and South Donegal, which, on account of 'lithological similarity to those of the North-west of Scotland, were supposed to be of Archaean age, are now known to be intrusive rocks, newer than the adjoining mica-schists, quartzites and limestones, and are represented accordingly: Other less important differences have also been duly noted upon the present map, with a view to bringing this into line with information obtained up'to 1900. It remains for me to explain that, having in view a class of readers more conversant, perhaps, with the industrial aspects of the subjects than the scientific, I have avoided, as much as pos sible, geological expressions which might be thought too technical, and have distinguished by capital initials, and otherwise, some which were unavoidable. To facilitate reference, paragraph head ings and other means have abundantly been used.
The granitic gneisses of Erris (north Mayo), of the Ox Mountains, Connemara, and South Donegal, which, on account of 'lithological similarity to those of the North-west of Scotland, were supposed to be of Archaean age, are now known to be intrusive rocks, newer than the adjoining mica-schists, quartzites and limestones, and are represented accordingly: Other less important differences have also been duly noted upon the present map, with a view to bringing this into line with information obtained up'to 1900. It remains for me to explain that, having in view a class of readers more conversant, perhaps, with the industrial aspects of the subjects than the scientific, I have avoided, as much as pos sible, geological expressions which might be thought too technical, and have distinguished by capital initials, and otherwise, some which were unavoidable. To facilitate reference, paragraph head ings and other means have abundantly been used.