1 66 



SCIENTIFIC NKWS. 



[Sept. 1st, 1887. 



and is at once seized by the rotating cones and is driven 

 upwards. But the mass of steel does not emerge at the top as a 

 solid, but in the form of the hollow steel tube which Siemens 

 laid before the meeting. Prof. Neesen gave the following 

 explanation of this striking result : owing to the properties of 

 the glowing steel, the rotating rollers seize upon only the outer 

 layer of the steel cylinder and force this upwards, while at the 

 same time the central parts of the cylinder remain behind. The 

 result is thus exactly the same as is observed in the process of 

 making glass tubes out of glass rods. 



THE GEOLOGICAL SOCIETY. 



T a meeting held on June 23rd, Professor J. W. Judd, F.R.S., 

 president, in the chair, the following communications were 



A 



read: 



1. "On Nepheline Rocks in Brazil, with special Reference to 

 the Association of Phonolite and Foyaite." By Orville A. Derby, 

 Esq., F.G.S. 



The author referred to the phonolites and associated basalts 

 of Fernando Noronha, a deep-sea island off the north-eastern 

 shoulder of the continent of South America. Nepheline rocks 

 of a somewhat different character are abundantly developed on 

 the mainland, and under conditions favourable for throwing 

 light on the relations existing between the granite type, foyaite, 

 and the other members of the group. There are some mountains 

 near Rio de Janeiro composed of these rocks, as is also the peak 

 of Itatiaia, 3,000 metres high, the loftiest mountain of eastern 

 South America. A cursory examination of some of these locali- 

 ties having shown an apparent relation between foyaite, phono- 

 lite, trachyte, and certain types of basalt, Mr. Derby determined 

 to visit the Caldas region, where a railway under construction 

 gave unusual facilities for examining this series. A fine develop- 

 ment of foyaite, phonolite, and tuff was found, associated with 

 several types that have not yet been met with in the other 

 localities. The existence of a leucite basalt was recognised. 



The bulk of the paper was devoted to a detailed description 

 of these railway-sections, and the following deductions are 

 drawn :— (i) The substantial identity, as regards mode of 

 occurrence and geological age, of the Caldas phonolites and 

 foyaites. (2) The connection of the latter through the phono- 

 lites with a typical volcanic series containing both deep-seated 

 and aerial types of deposits. (3) The equal, if not greater 

 antiquity of the leucite rocks as compared with the nepheline 

 rocks, whether felsitic, as phonolite, or granite as foyaite. (4) 

 The probable palaeozoic age of the whole eruptive series. 



In the discussion which followed the President remarked that 

 it was seldom that a paper containing such important facts was 

 presented to the Society. It was reserved to Mr. Derby to have 

 proved that plutonic rocks containing nepheline (foyaite) passed 

 into volcanic masses which were true phonolites. This Mr. 

 Derby had clearly established by observations in the field. He 

 liad also shown that leucite existed in rocks of palaeozoic age, 

 -thus rendering untenable the last stronghold of those who 

 insisted on making geological age a primary factor in petro- 

 graphical classification. He alhided also to the value of the 

 independent determinations of Professor Rosenbusch. 



2. " Notes on the Metamorphic Rocks of South Devon." By 

 Miss Catherine A. Raisin, B.Sc. Communicated by Professor 

 T. G. Bonney, D.Sc, LL.D., F.R.S., F.G.S. 



This communication consisted mainly of detailed observa- 

 tions, supplementary to those published by Professor Bonney 

 in the Society's Journal for 1S84, on the slaty and metamorphic 

 rocks of South Devon in the neighbourhood of Salcombe 

 ■estuary. In the first part of the paper, details were given of the 

 sections exposed around the estuary, at Hope Cave to the west- 

 %vard, and in several localities to the eastward as far as Hall 

 Sands, all confirmative of Professor Bonney's views, and show- 

 ing that the slaty beds to the northward do not pass into the 

 mica and chlorite schists to the south, but are separated from 

 the latter by a line of faults. Descriptions were then given of 

 microscopic slides from various parts of the metamorphic rocks. 

 Some of these showed the action of secondary forces. The 

 effects of lateral pressure in producing cleavage-planes and a 

 kind of jointing were also commented upon. 



3. " On the Ancient Beach and Boulders near Braunton and 

 Croyde in Nortli Devon." By Professor T. M'Kenny Hughes, 

 M.A., F.G.S. 



The author observed that amongst the raised beaches of S.W. 

 England, we generally find included the sand cliffs of Saunton 

 Down and Middleborough on the coast west of Barnstaple. 

 These deposits possess a further interest owing to the occur- 

 rence at their base of large boulders. In 1866 Mr. Spence Bate, 

 in opposition to the prevailing views, concluded that the so- 

 called raised beach is the undestroyed remnant of an extensive 

 district of wind-borne sand similar to that which now exists on 

 Braunton Burrows. The points to which attention was invited 

 are as follows : — 



(i) Is this deposit on the southern slope of Saunton Down a 

 raised beach ? 



(2) Were the above-mentioned boulders carried to their present 

 position by ice ? 



The paper was fully illustrated by diagrams, showing the 

 relations of the recent deposit, and by figures showing the 

 mode of occurrence of three of the most remarkable boulders. 

 The conclusions were : — 



( I ) That the ancient beach of Saunton Down and Croyde is not 

 a raised beach in the ordinary acceptation of the term. The top 

 is subaerial talus, the middle part is blown sand, the base only 

 marine, and the marine part is not above the reach of the waves 

 of the sea at its present level. (2) The boulders of granite 

 and felsite which occur at the base of the ancient beach were 

 transported to their present position by the waves of the sea. 

 Such as are of local origin could have reached the sea by the 

 ordinary processes of denudation ; such as are possibly of 

 northern origin could have been carried down the Irish Channel 

 on bergs, and been thrown up by the sea to their present posi- 

 tion at any period subsequent to their transportation southwards 

 by ice ; but their presence does not imply any local glacia- 

 tion. 



4. " Notes on the Formation of Coal-seams, as suggested by 

 evidence collected chiefly in the Leicestershire and South 

 Derbyshire Coal-field." By W. S. Gresley, Esq., F.G.S. 



The author's principal object in this paper was to bring for- 

 ward evidence in opposition to the view now generally accepted 

 that coal-seams were formed from vegetation growing on the 

 spot. 



He showed that during a very extensive experience he had 

 only once or twice detected stems passing into a bed of coal 

 and connected with the Stigmaria-roots in the underclay. If, 

 as was generally stated, the Stigmariae were the roots of the 

 trees that formed the coal, such instances ought to be common. 

 Not only, however, were they very rare, but the abundance of 

 the StigmaricC was extremely variable, and these roots, instead 

 of becoming more thickly matted together in the uppermost 

 part of the underclay, as they should be if they were roots of 

 the coal-forests, were generally distributed, as a rule, through- 

 out the clay in a manner that showed them to have been, in all 

 probability independent organisms. Stigmarian roots, when 

 found connected with a stem, were more often on the top of the 

 coal-seam than at the bottom. 



REVIEWS OF BOOKS. 



Progress. By James Piatt. London : Simpkin, Marshall, and 

 Co. 



Time was whefi the bulk of mankind believed that the world 

 was gradually and continuously getting worse. A golden age of 

 peace, plenty, and content, had been, so they believed, succeeded 

 by an age of silver (a little inferior), and that, again, in turn by a 

 brazen and an iron age. In the earlier portion of the modern 

 ages there set in a change of opinion. The doctrine of " pro- 

 gress " was preached ; we were told that the world, and especially 

 mankind, was constantly and in all respects improving. And 

 when the theory of organic evolution was established by the 

 labours of Darwin and his coadjutors, it was rather hastily con- 

 cluded that the idea of progress had received its full scientific 

 consecration. 



From the title of this book we were led to expect an examina- 

 tion of the causes, the principles, and the limits, of progress. 

 We hoped that the author would have shown that mankind does 

 not move along one uniform track, but that it is capable of 

 turning to the right or to the left in endless manners and matters ; 

 capable, too, of advancing in some particulars whilst remaining 

 stationary or retrograding in others. We expected, further, that 

 he would have explained when, where, and how, the tendency to 



