1-23 REPORT — 1872. 



rich in sodium, to he sublimated by Tolcauic processes. The chloride of sodium 

 derived from the sea is separated bj^ the chemical actions of the volcano. Chlorine 

 unites with hydrogen, iron, &c. ; sodium plays its part in the formation of sodalite. 

 Sea-water is the great source of volcanic phenomena, as well in the mechanical as 

 in the chemical point of view. Steam raises the melted matter upwards to the 

 border of the crater; steam and sodium operating on the !lava originate new 

 minerals. So sublimations will solve many problems in regard to new and ancient 

 mineral formations, not to be explained either by supposing a merely aqueous pro- 

 cess, nor by crystallization out of a molten iluid. 



Twenty j'ears ago Prof. Scacchi of Naples did suggest the sublimation of silicates 

 at Vesuvius, without producing sufficient proofs to secure belief in this seemingly 

 incredible fact. The pyroxenes implanted on the volcanic h;ematite in the neigh- 

 bourhood of our lake of Laach, and the matter ejected by Vesuvius during the 

 last eruption, place this remarkable fact beyond doubt. 



On the Coal- and Iron-Mines of the Arlgna District of the Connaufjht Coal- 

 measures, Ireland, By T. A. Eeauwin, F.G.S. 



The author first gave a sketch of previous writings upon this district, and 

 acknowledged his indebtedness to the Geological Survey of Ireland for assistance 

 in his researches. 



The shales overlying the Upper Limestones of the district wqre surmised by the 

 author to belong to the Yoredale series. Over these there are grits and shales, with 

 three seams of coal, which the author referred to the Gauuister series, remarking 

 that a bed of true " gannister " occurred there. 



The coal-field was divided into three districts by the author, each of wliich Vv as 

 separately described. He noticed at some length the clay, ironstone bands, and 

 nodules, which occur over a much larger area than do the coals. The ironstone is 

 richer and purer than most of the English clay-ironstone. 



The coals contained an average of 77 per cent, of carbon, and the limestone an 

 average of 40 per cent, of metallic iron. 



The author believed that the time had come for a vigorous and scientific explo- 

 ration of the district, which he felt convinced w^ould soon become, ns Sir R. Kane 

 had long ago predicted, " an important centre of industry Cor the interior of the 

 country." 



On the Occurrence of a British Fossil Zenglodon at Barton, Hants, 

 Bij II. G. Seelet, F.G.8. 



On certain QMariz-Kodulos occurring hi the Crystalline Schists near Killin, 

 Perthshire. By Robeet Sim, M.D. 



On the Suh-Wealden Exiiloration. By W. Toplet, F.O.S. 



The author stated that this paper was submitted to the Section with the view of 

 giving some information as to an experiment just being commenced to explore, by 

 boring, the rocks imderlying the Weald of Sussex, especially to reach and 

 ascertain the nature of the paleozoic rocks. This undertaking has been planned 

 by Mr. Henry Willett, in honour of the visit of the Association to Brighton. 



The author first described the general structure of the Weald, illustrating his 

 remarks by reference to the roclis exposed along the Loudon and Brighton Raihvay. 

 The lines of disturbance traversing this area were also described ; and particular 

 reference was made to the lowest known beds of the district (the Ashburnliain beds), 

 which are brought up to view by the main anticlinal on the north of Brightling. 

 The ascertained thickness of these Ashburnhnm beds was slated to be about 350 

 feet, and the lowe.'-t known beds were shown to lie close to the surface in Eounden 

 Wood; near Brightling. 



