October 25, 1901.] 



SCIENCE. 



635 



tree, which was penetrated by calcite, ex- 

 tended to about five feet above this old soil, 

 and above this was a hollow in the basalt 

 about forty feet high, which evidently rep- 

 resented a cast of the tree. The conditions 

 indicated an old lava flow which had later 

 undergone a certain amount of disintegra- 

 tion and afforded a soil upon which the 

 tree established itself; then a period suc- 

 ceeded during which the tree grew until it 

 reached a diameter of eight feet and an es- 

 timated height of eighty feet ; then an out- 

 flow of lava around the tree was followed 

 by an interval during which the decay of 

 the tree took place ; and finally the outflow 

 of the sheet of basalt, which covered and 

 sealed up the top of the hollow left by the 

 decay. 



The geology of the nearly related north 

 coast of Ireland also received its due share 

 of attention, papers being presented by 

 Messrs. McHenry and Kilroe, of the Geo- 

 logical Survey, on ' The Relations of the 

 Old Red Sandstones of Northwest Ireland 

 to the Adjacent Metamorphic Rocks and. 

 their Similarity to the Torridon Beds of 

 Sutherland,' and on 'The Relation of the 

 Silurian and Ordovician Rocks of N"orth- 

 west Ireland to the Great Metamorphic 

 Series.' This latter paper, which attempted 

 to refer the metamorphic rocks of Mayo 

 and Galway to the Lower Silurian period, 

 awakened a considerable amount of discus- 

 sion and some adverse criticism, since, if 

 the views of the authors were correct, it be- 

 came a difficult matter to explain the pres- 

 ent difference between these rocks and the 

 fossil-bearing Lower Silurian beds of ad- 

 joining areas. Papers were also read by 

 Mr. G. H. Kinahan, entitled, ' Notes on 

 the Irish Primary Rocks and their Associ- 

 ated Granite and Metamorphic Rocks,' and 

 on ' Some Laccolites in the Irish Hills.' 



Papers on the geology of foreign areas 

 were comparatively few. Miss Raisin gave 

 an account of a lithological study of volcanic 



rocks collected on Perim Island and took 

 occasion to refer to the geological history 

 of the Red Sea area, inferring that this 

 sea formed part of the Great Rift Valley, 

 extending from Lake Tanganyika to the 

 Jordan and displaying at many places vol- 

 canic outbursts on a large scale, at different 

 periods. Dr. Logan Jack, formerlj^ head of 

 the Geological Surve}'^ of Queensland, gave 

 an account of the ' Artesian Water in the 

 State of Queensland. ' The greater part of 

 the western interior of Queensland is com- 

 posed of soft beds of lower Cretaceous rocks 

 so disposed as to crop out on the western 

 flanks of the coast range where the elevation 

 and rainfall are greater than in the downs 

 of the west. Along the eastern margin of 

 the Cretaceous outcrop is a porous sand- 

 stone whose outcrop forms a belt of from 

 five to twenty-five miles in width, the strata 

 dipping at a low angle beneath the clayey 

 and calcareous beds which form the sur- 

 face of the downs. The conditions accord- 

 ingly seemed favorable for boring artesian 

 wells, and a successful beginning of the de- 

 velopment of a water supply of this nature 

 was made under the supervision of Dr. Jack 

 in 1885 and up to June, 1900, one hundred 

 and eighty-five miles of boring had been 

 made in the district, the majority of the 

 borings being successful. Owing, however, 

 to the fact that the artesian basins are im- 

 perfect, a considerable amount of leakage 

 takes place from them, the water probably 

 finding an outlet into the Great Australian 

 Bight or the Gulf of Carpentaria. 



In a paper on ' The Physical History of 

 the Norwegian Fiords,' Professor Edward 

 Hull described six important stages in the 

 development of these characteristic features 

 of the Norwegian coast. First there was the 

 continental condition with archsean rocks ; 

 when the river erosion began, and this was 

 succeeded by a second stage of partial sub- 

 mergence in early Silurian times. The 

 third stage was the elevation of the land 



