Microscopical studies of Tasmanian rocks

The delicate methods of modern microscopical petrology have added greatly to our knowledge of igneous rocks. Very little work of this description has hitherto been attempted in Tasmania, but the present studies, undertaken in connection with the Launceston Microscopical Club, have been entered upon in the hope of throwing additional light upon the genesis and intimate structure of our eruptive rocks. It is proposed to continue the descriptions from time to time as materials and opportunity permit, and as they must at first necessarily partake of the nature of preliminary work, remarks upon their classification will be withheld till sufficient progress has been made to justify generalisations. A glance at the current literature of our science suffices to show that the microscope in petrology is each year enlarging the boundaries of its conquests, and it is hoped that the present contributions will prove helpful to the stratigraphical geologists of this island.