 | British Association for the Advancement of Science - 1836
...the concentric arrangement of the beds of greenstone in Donegal, and the occurrence of quartz reck between two beds of greenstone, the quartz being columnar,...expressing his belief that the trachytic porphyry of Sandy Brae in Antrim was nothing more than this ochre indurated by heat, Mr. Griffith adduced the fact of... | |
 | British Association for the Advancement of Science - 1836
...by greenstone, the concentric arrangement of the beds of greenstone in Donegal, and the occurrence of quartz rock between two beds of greenstone, the...the granite is concealed by debris. After noticing brirriy the ochre In-cU which so often separate the beds of basalt, and expressing™ •fcelirC that... | |
 | 1835
...by greenstone, the concentric arrangement of the beds of greenstone in Donegal, and the occurrence of quartz rock between two beds of greenstone, the quartz being columnar, the trap " Professor Sedgwick pointed put, in confirmation of Mr. Griffith's views, many striking instances... | |
 | 1835
...by greenstone, the concentric arrangement of the beds of greenstone in Donegal, and the occurrence of quartz rock between two beds of greenstone, the...expressing his belief that the trachytic porphyry of Sandy Brae in Antrim was nothing more than this ochre indurated by heat, Mr. Griffith adduced the fact of... | |
 | Philip Dixon Hardy - 1836
...by greenstone, the concentric arrangement of the beds of greenstone in Donegal, and the occurrence of quartz rock between two beds of greenstone, the quartz being columnar, the trap :hove and below it not. IB Slieve Gullin greenstone and granite were stnted to be actually mixed together,... | |
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... the change they effect in their structure. Mr. Griffith next described the older and newer trap districts, mentioning many interesting particulars connected with them, such as the capping of quartz rock by greenstone, the concentric arrangement of... 