Feb. II, 1875J 



NATURE 



299 



la^us, form a well-marked independent group of the Macropoid 

 Marsupialia. — Mr. Sclater read notices of some rare parrols now 

 living in the Society's Gardens, and called special attention to 

 examples of Goflin's Cockatoo (Cacntua qof/ini), and Bouquet's 

 Parrot (C/irvsolis bouqiicli), as being amongst the rarest speci- 

 mens. — A communication was read from Mr. Edward Bartlett, 

 curalor of the Museum and Public Library, Maidstiine, contain- 

 ing a list of the mammals and biros collected by Mr. Waters in 

 Madagascar, amongst which was a fine adult specimen of the 

 Madagascar River-hog {Potatiwclun lis edwardsi). — A communi- 

 cation was read from Mr. E. P. Ramsay, containing remarks on 

 the original skin of J'liloiior/iynchus rawtnlfyi, which he regarded 

 as a hybrid between the .Satin Bower-bird (PeiLuwr/iyiuJuis liolo- 

 (cruais) and the Regent-bird {Scriciiliis chrvsccephaliis). — Mr. R. 

 Bowdler .Sharpe read a paper entitled "Contributions to the 

 Ornithology of Madag.iscar, " being the fourth communication on 

 tiie same subject made to the Socieiy. This paper contained 

 descriptions of a new Accipitrine form proposed to be called 

 Enliiorchis astiir, a new species of Aldornis, proposed to be 

 called A. crosshyi, and a new foim of Nectarini da;, to which 

 the name Neodrc/ums coruscans was assigned. — Dr. Giinther, 

 F. K.S., read a paper on some mammals recently collected by 

 Mr. Crossley in Madagascar, amongst which were a new Lemur, 

 proposed to be called Chirogaleus trkJiolis, and a new form of 

 rodent, belonging to the Murida;, for which the name Brauhy- 

 tarsoniys albicauda was suggested. 



Geological Society, Jan. 7. — Mr. John Evans, F.R.S., pre- 

 sident, in the chair. — 'I'he following communications were read : 

 — On the stractute and age of Arthur's Seat, Edinburgh, by M r. 

 John W. Judd. The author said that Arthur's Seat, so long the 

 battle-ground of rival theorists, furnished in the hands of Charles 

 Maclaren a beautiful illustration of the identity between the 

 agencies at work during past geological periods and those in 

 operation at the present day. One portion, however, of Mac- 

 laren's masterly exposition of the structtire of Arthur's Seat, that 

 which rcq.ires a stcond period of eruption upon the same site, 

 but subsequent to the deposition, the upheaval and the denuda- 

 tion of the whole of the Carboniferous rocks, is beset with the 

 gr.ivest difficulties. The Tertiary and Secondary epochs have in 

 turn been piofosed and abandoned as the peiiod of this supposed 

 second period of eruption ; and it has more recently been placed, 

 on very questionable grounds, in the Permian. The antecedent 

 improbabilities of this hypothesis of a second period of eruption 

 are so great, that it was abandoned by its author himself before 

 his death. A careful study of the whole question by the aid of 

 the light thrown upon it in comparing the stiucture of Arthur's 

 Seat with that of many other volcanoes, new and old, shows the 

 hypothesis to be alike untenable and unn^icessary. The supposed 

 proofs of a second per.od of eruption, drawn from the position of 

 the central lava column, the nature and relations of the frag- 

 mentary materials in the upper and lower parts of the hill respec- 

 tively, and the po.^idon of certain rocks in the Lion's Ilaunch, 

 all break down on re-examination. While, on the other hand, an 

 examination of Arthur's Seat, in connection with the contem- 

 poraneous volcanic rocks of Forfar, Fife, and the Lothians, shows 

 that in the former we have the relics of a volcano which was at first 

 submarine but gradually rose above the Carboniferous sea, and was 

 the product of a single and almost continuous series of eruptions. 

 — "The Glaciation of the Southern Part of the Lake-district, 

 and the Glacial Origin of the Lake-basins of Cumberland and 

 Westmoreland " (second paper), by Mr. J. Clifton Ward. The 

 directions of ice-scratches in the various dales having been 

 pointed out, the course of the several main glaciers was described, 

 and it was shown how they must have become confluent in all 

 the lower ground, forming a more or less continuous ice-sheet, 

 which overlapped most of the minor ridges parting valley from 

 valley, and was frequently forced diagonally across them. The 

 po.-itions of certain ice-grooves having an abnormal direction 

 were described ; in several cases these cross lofty ridges at right 

 angles to their direction, and generally at passes or depressions 

 along a water-shedding line. Most of those noticed had a gene- 

 rally east and west direction, and occurred at varying heights, 

 from 1,250 to 2,400 feet. The author, while acknowledging the 

 difficulty attendant upon any explanation, was inclined, though 

 somewhat doubtfully, to regard these abnormal m.arkings as due 

 to floating ice, during the great period of interglacial submer- 

 gence. The moraines were all believed to belong to the last set 

 of glaciers. The subject of the " Glacial origin of Lake-basins " 

 was then entered upon, and the following lakes discussed by 

 means of diagrams drawn to scale, ihovving lake-depths, 



mountain outlines, and the thickness of the ice : — Wastwater, 

 Grasmere, Easdale, Windermere, Coniston, and Esthwaite 

 together with several mountain tarns. In the case of Wastwater 

 the bottom was shown to run below the level of the sea for a 

 distance of a mile and a quarter, and the deepest point to be just 

 opposite the spot at which the only side valley joins the main one. 

 While the greatest depth of the lake is 251 feet, the thickness of 

 the old glacier-ice must have been fully 1,500 ; and, all points 

 considered. Prof. Ramsay's theory of glacial erosion seemed to 

 the author certainly to be upheld. In like manner, the same 

 theory was thought to account for the origin of the other lakes 

 mentioned, such ones as Windermere and Coniston being but 

 long narrow grooves formed at the bottom of pre-existing valleys. 

 -Mountain tarns v/ere held to be due sometimes wholly to glacial 

 erosion, sometimes to this combined with a moraine dam, and 

 occasionally to the ponding back of water by moraines alone, 

 or luoraine-like mounds formed at the foot of snow-slopes. 



Chemical Society, Feb. 4.— Prof. Odling, F.R.S., in the 

 chair. — A communication from Mr. G. Whewell, entitled "Test 

 for Carbolic Acid," and a note on the action of anhydrous ether 

 on titanic tetrachloride, by Mr. P. P. Benson, were read. Two 

 crystalline compounds are obtained in this reaction : the one, 

 Lolling at 105" to 120° C, and melting at 42" to 48° C, has the 

 composition TiCl4 (CjUju) O ; the other, titanium ethyl tri- 

 chlorhydrine, TiClj (C.illsO), melts at 76" to 78" C, and boilsat 

 1S6" to iSS°C. — The "last paper was by Mr. W. H. Perkins, 

 F. R. S., on dibromacetic and glyoxylic acids. 



Institution of Civil Engineers, Feb. 2.- — Mr. Thos. E. 

 Harrison, president, in the chair. — The paper read was " On the 

 origin of the Chesil Bank, and on the relation of the existing 

 beaches to past geological changes, independent of the present 

 coast action," by Prof. Joseph Prestwich, F.R.S., &c. — This 

 remarkable bank of pebbles, extending from Portland to 

 Abbotsbury, a distance of nearly eleven miles, was described 

 with great accuracy by Sir John Coode, M. Inst. C.E., in 1S53 

 (c'ii/e "Minutes of Proceedings Inst. C.E.," vol. xii. p. 5:0). 

 It was then 43 feet high and 600 feet wide at the south end, 

 decreasing to 23 feet high and 510 feet v.'ide at the north end. 

 The pebbles diminished in size from Portland to Abbotsbury. 

 Sir John Coode also stated that the shingle consisted chiefly of 

 [lepples of chalk-flint, with a small proportion of others of red 

 sandstone, porphyry, and jasper, none of which could have been 

 derived from local rocks. In order to determine their origin, he 

 examined the coast from Portland to Start Point, and traced the 

 Hints to the chalk clifiTs between Axinouth and Lyme, and the 

 red sandstone, porphyry, and jasper pebbles to the new red 

 sandstone of Budleigh .Salterton and other places in Devon- 

 shire ; whence he concluded thai the only source from which the 

 shingle o( the Chesil Bank could have been derived was between 

 Lyme Regis and Budleigh, and that it was propelled eastward 

 along the coast to the Chesil Bank by the action of wiird- waves, 

 due to the prevalent and heaviest seas. The objection to this 

 view urged at the time by the Astronomer Royal was, that the 

 largest shingle occurred at the Portland end of the beach, or the 

 most distant part from which it had travelled. More recently 

 an old "raised beach," standing from twenty-one to forty-seven 

 feet above the present beach, had been discovered on the Bill 

 of Portland, and Prof Prestwich showed that this beach con- 

 tained all the materials found in the Chesil Bank, including also 

 numerous chert pebbles from the Upper Greensand of the cliff 

 between Biidport and Sidmouth. This raised beach was not 

 due to any existing agency, but to causes in operation at a geo- 

 logical period so remote as the end of the glacial period, and 

 before the land had assumed its present position and shape. 

 Remnants of this beach could be found in or on the present 

 cliffs, at intervals from Brighton to the coast of Cornwall, being 

 more numerous in Devon and Cornwall, as the rocks were harder, 

 than among the softer strata of Dorset and Hants, where, with 

 few exeptrons, the old line of cliff had been worn back and 

 deeper bays formed. The travel of the shingle of this old 

 beach was generally like that of the present beach, from west to 

 east. The author considered that the action of the " Race " off 

 Portland, and of the tidal waves durtng storms, combined to 

 drive the shingle of the old beach at the Bill, and of that portion 

 of it which must be spread on the sea-bed westward of Port- 

 land, on to the south end of the Chesil Bank, whence the 

 shingle was driven northward to Abbotsbury and Burton, by 

 the action of the wind-waves, having their maximum force from 

 the S.S. W., a direction which he showed to be the mean of the 

 prevalent winds. Here these wmd-waves became parallel with 



