66 



NATURE 



[March 9, 191 1 



urged that the utmost possible use should be made of 

 paheogcographical maps, both as a means of expressing 

 ascertained fact and as affording a focus for new critical 

 investigation. The association of the phases of earth- 

 movement with igneous activity was next briefly treated, 

 as also the connection of movement with rock-structure 

 and existing physiography. Finally, geographical evolu- 

 tion was examined as the spur to organic evolution, and 

 it was urged upon palasontologists that they should 

 endeavour to ascertain to what r'XtiMit f)cri()ds of slow or 

 rapid evolution corresponded with epochs of physical 

 change. 



February 22. Prof. W. W. Watts, F.R.S., president, 

 in the chair. — R. H. Rastall : The geology of the dis- 

 tricts of Worcester, Robertson, and Ashton (Cape Colony). 

 After a brief description of the physiography of the dis- 

 trict and the general sequence of the rocks composing it, 

 in which the incompleteness of the stratigraphical record 

 is especially noted, a detailed account is given of the 

 structure and characters of the Malmesbury rocks of 

 Worcester and the region near that town. These are 

 shown to include a lower and an upper sedimentary series, 

 predominantly gritty and slaty respectively, and evidently 

 of great thickness, probably more than 20,000 feet. The 

 upper division is pierced by granitic dykes, which have 

 been subsequently crushed and foliated, forming " phyllite 

 gneiss." Certain bands of limestone are metamorphosed 

 by them to pure white marble. The distribution and 

 characters of the rocks of the Cape and Karroo systems 

 are only dealt with, in so far as they throw light on the 

 principal subject of the paper, but a fairly full descrip- 

 tion is given of the occurrences of Enon Conglomerate, 

 which is shown to occupy a series of isolated basins 

 arranged along an east-and-west line, and to lie with a 

 strong discordance upon all the older rocks. After a 

 careful discussion of all the available evidence, it is con- 

 cluded that the Worccster-Swellendam Fault, which has a 

 maximum throw of probably 10,000 feet, is in great part 

 of post-Cretaceous age, although there are indications of 

 earlier movement along the same line of fracture. From 

 a study of the dominant trend-lines of south-western Cape 

 Colony, it is concluded that the district in question is 

 situated at or near the central line of the syntaxis of two 

 great sets of folds at right angles, which have assumed a 

 fan-shaped arrangement in plan, and that the great fault 

 i.^ a line of fracture and subsidence running transversely 

 across these lines of folding.— Baron Ferencz Nopcsa, 

 jun. : Geology of northern Albania. The author had 

 examined the greater part of the province of Skutari in 

 western Turkey, and recognised three distinct structural 

 units, namely, the north Albanian platform, the folded 

 Cukali, and the eruptive region of Merdita. In the first 

 region Mesozoic limestone of all periods predominates, in 

 the second region Mesozoic radiolarian chert is found, 

 while in the third region Mesozoic clastic rocks, volcanic 

 tuffs, and eruptive masses are abundant. The first and 

 third units are not folded, but are, at least in part, over- 

 thrusts from the north and south respectively above the 

 second (intermediate) unit, which is strongly folded. In 

 northern Albania Upper Carboniferous and Permian rocks 

 are also distinguishable, and there is an Eocene flysch. 



Zoological Society, February 21. — Dr. A. Smith Wood 

 ward, F.R.S., vice-president, in the chair. — R. 

 Lydekker : Tragelaphus buxtoni, an antelope obtained 

 by Mr. Ivor Buxton in Abyssinia. — E. G. Bouleng^er : 

 Varieties of the spotted salamander (_Salamandra macu- 

 losa). One of the principal results of the author's study 

 was to lay greater stress on the disposition of the spots 

 than on their actual form, size, or colour, and to define 

 two principal forms in Central Europe, which had not 

 previously been separated with sufficient precision, notwith- 

 standing their well-marked geographical distribution. The 

 author further dealt with some of the experiments of Dr. 

 Kammerer, of Vienna, and the conclusions arrived at by 

 him with regard to coloration in relation to environment. 

 — G. A. BoMleng^er : A collection of fishes from the Lake 

 Ngami basin, Bechuanaland, made by Mr. R. B. Woos- 

 nam. — Dr. F. D. Welch : Gibbons of the genus Hylo- 

 bates, and on a Siamang gibbon, recently living in the 

 society's gardens, with notes on skins in the British 

 Museum (Natural History). 



NO. 2158. VOL. 861 



Manchester. 

 Literary and Philosophical Society, February 21— Mr. 



P'rancis Jones, president, in the chair. — Dr. Alfred Holt : 

 The boric acids. l'2xperiments were described on (i) tho 

 rate at which orthoboric acid loses water when heated to 

 different temperatures ; (2) the changes in the vapour 

 density of orthoboric acid on heating ; (3) the freezing 

 points of solutions of ortho-, meta-, and pyroboric acid ; 

 and (4) melting points of mixtures of orthoboric acid and 

 boric anhydride. From these experiments the following; 

 conclusions were drawn : — (i) metaboric acid is probably 

 a definite compound ; (2) no evidence is found for the 

 existence of boric acids containing less water than the 

 meta acid ; (3) only orthoboric acid exists in solution, and 

 it is present in simple molecules ; (4) metaboric acid can- 

 not be regarded as an equimolecular mixture of ortholxiric 

 acid and boric anhydride ; (5) fused mixtures of ortho- 

 boric acid and boric anhydride, in which the molecular 

 ratio of the latter to the former compound exceeds 4:1, 

 can exist in a vitreous metastable and crystalline stable 

 form. — J. E. Myers and Dr. A. Holt: The hydration ol 

 metaphosphoric acid. Experiments were described b) 

 which it was shown that pyrophosphoric acid is formed as 

 an intermediate compound in the hydration of metaphos- 

 phoric arid. It was further shown that the hydration di<i 

 not take place according to any simple scheme, and a 

 method of estimating meta acid in a solution of all thre< 

 varieties by means of barium chloride was described, 

 From the depression of the freezing point of aqueous solu- 

 tions of various varieties of pyro and meta acids, i1 

 appears that, when these acids are prepared by dehydratior 

 of orthophosphoric acid, there occurs association of the 

 molecules, but when prepared by decomposition of the lead 

 salts by hydrogen sulphide, simple molecules result. Th< 

 peculiar " crackling " phenomenon which accompanies the 

 solution of one form of meta acid was shown. 



Dublin. 

 Royal Irish Academy, February 11. — Dr. F. A. Tarleton, 

 president, in the chair. — W. M'Fadden Orr : Extension o! 

 Fourier's and the Bessel-Fourier theorem. The authoi 

 shows by application to some illustrative physical problem! 

 how certain defects as to uniqueness and differentiabilit) 

 in the expansions of the former pap>er (Proc. Roy. Irish 

 Acad., vol. xxvii.. A, 11) may be remedied. These prob- 

 lems include the motion of the system consisting of i 

 stretched elastic string and a number of elastically con 

 nected particles at each end, in extension of a simple case 

 considered by Lord Rayleigh (" Theory of Sound," § 135) 

 the analogous problem involving the motion of a circulai 

 or annular membrane, and analogous problems in heai 

 conduction. The expansions are also extended so as tc 

 apply to the same vibrating systems when subject through 

 out to viscous forces, in which case the displacement ol 

 the string satisfies the equation 



(i^4>ldfi = c^d-<t>ldx'- -fd<t>ldt +gd^<f,ldx^df. 



— A. W^ Conway : The application of quaternions to some 

 recent developments of electrical theory. Two example) 

 of quaternion treatment are given for the purpose of shoW' 

 ing the su{>eriority of this method over vectors, by con^ 

 sidering two cases in which the latter would lead to grea! 

 complication. The subjects taken are Poincar^'s Fredholr 

 solutions for Hertzian waves, and Einstein's an 

 Minkowsky's formulae of relativity. — Rev. M. F. Eg:*" 

 The linear complex and a certain class of twisted curves 

 on twisted curves such that the degree of any cycle of thr 

 curve is equal to its class. Relations between such curve; 

 and null-systems in three-space. 



February 27. — Dr. F. A. Tarleton, president, in the 

 chair. — R. Lloyd Praegrer : Clare Island survey : repon 

 of progress during 1910. During the second year's field 

 work on Clare Island and its neighbourhood great advanere; 

 have been made. About fifty workers visited the distrid 

 during the year, for periods ranging from one to three 

 weeks. Simultaneously with this report, the first instal 

 ment of the results of the survey are presented to the 

 academy. It is intended to finish the field-work during 

 the present year. In connection with the Clare Islam 

 survey, the following papers were read : — N. Col^a" 

 Marine mollusca. The author gives a very full accoun! 

 of the marine mollusca collected during the vears iqoq ant 



