January 23, 1908J 



NATURE 



287 



tion was explained by Mr. J. W. Anowsmith. Eight or 

 nine years ago, about 400;. was collected yearly to for- 

 ward higher education in Bristol, and the amount is now 

 nearly Oooi. per annum. In all, the society had collected 

 a sum of 4732/. Speaking as to the University itself, Mr. 

 Arrowsmith said the promise of Mr. H. O. Wills, 

 announced in N.-vture last week, was satisfactory to all, 

 and all welcomed it very heartily and with deep gratitude 

 to Mr. Wills. But the 100,000/. gift is not everything. The 

 amount aimed at before the Privy Council is asl-ced for the 

 charter is 250,000/. The aggregate sum of 30,000/. was 

 promised at the dinner a year ago. The sums were : — 

 Lord Winterstoke, 10,000/. ; Mr. J. S. Fry, 10,000/. ; Mr. 

 Frederick Wills, 5000/. ; and Mr. F. J. Fry, 5000/. Adding 

 for buildings and endow'ments in connection with Uni- 

 versity College the sum of 55,000/., a total of 85,000/. is 

 reached. Add to that the 100,000/., and 185,000/. is 

 obtained. Mr. Arrowsmith said that a friend, since he 

 had been in the building, had added another 10,000/., 

 giving a total in hand or promised of 195,000/. It is 

 obvious, therefore, that a sum of 55,000/. must be secured 

 before the charter can be sought. Four sums each of 

 1000/. from Mr. Charles Thomas, Mr. Edvi-ard Robinson, 

 Mr. Hiatt Baker, and an anonymous benefactor have also 

 been offered. It should not be long, therefore, before the 

 quarter of 'a million required for the university is raised 

 by the men of wealth in Bristol who realise the value of 

 highir education. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, December 12, 1907.— "The Effects of 

 Temperature and Pressure on the Thermal Conductivities 

 of Solids. Part ii. The Effect of Low Temperatures on 

 the Thermal Conductivities of Pure Metals and Alloys." 

 By Prof. C. H. Lees, F.R.S. 



The object of the work described in the present paper 

 was to extend tlie measurements of thermal conductivities 

 of metals and allovs made by Lorenz, Jager, and Diessel- 

 horst and others at temperatures between o" C. and 100° C. 

 down to the temperature of liquid air, and thus provide a 

 means of comparing the thermal and electrical conductivi- 

 ties of these substances over a much wider range of 

 temperature than has hitherto been possible. The method 

 adopted was a modification of that used originally by 

 Wiedemann and Franz. 



The results obtained arc tabulated, together with those 

 given for higher temperatures by Jager and Diesselhorst, 

 and they justify the following statements : — 



(i) TKe thermal conductivities of most pure metals 

 decrease as the temperature rises Avithin the rmige 

 — 160'' C. to 100° C. 



(2) The thermal conductivities of all alloys tested increase 

 as the temperature rises within the range — 160° C. to 

 100° C. 



Institution of Minine; and Metallurgy, January 16. — 

 Prof. William Gowland, president, in the chair. — The 

 \'aal River diamond diggings : Mungo Park. A brief 

 description of the diamondifcrous terrace deposits flanking 

 the course of the Vaal River. The author stated that the 

 diamonds obtained from the river gravels are, taken 

 collectively, probably the fineet stones obtainable, averaging 

 about 61. per carat as sold to buyers on the diggings. 

 Methods o{''working these deposits, and a few notes on 

 the general fronditions of digging, are dealt with in this 

 short paper. — The eruptive diamond-bearing breccias of 

 the Boshof district. South .'\frica : J. P. Johnson. A 

 paper describing the three occurrences of diamond-bearing 

 rock in the district, principally from a geological point 

 of view. Special attention is directed to the Iherzolite and 

 eclogite boulders, which contain in proportionate abund- 

 ance all the characteristic minerals of the eruptive 

 diamond-bearing breccia, and which the author thinks are 

 the more resistant portions of a rock which has gone to 

 form the bulk of the breccia, and was the real home of 

 the diamond. This Iherzolite-eclogite rock mav exist either 

 as a widespread consolidated formation occurring at great 

 depths or as a deep-seated molten magma, the former 

 condition being more likely. The author can see nothing 



NO. 1995, VOL. 77] 



in the breccia other than a purely fragmentary formation, 

 nor has he been able to detect traces of contact meta- 

 morphism either of the walls of the vent or of the included 

 boulders. He concludes, therefore, that the type of 

 volcanic phenomenon producing the peculiar features of 

 these diamond-bearing vents would be a geyser rather than 

 a volcano, more especially as there is not the least evidence 

 of any molten rock or lava having passed through them. 

 — The auriferous banded ironstones and associated 

 schists of South Africa : Owen Letcher. Five principal 

 mines working in the banded ironstone beds and associated 

 schists are passed under review in turn under the follow- 

 ing heads : — salient geological features ; occurrence of 

 gold in the formation ; m.ethods of mining and productive 

 and economic values ; and metallurgy of the scries. The 

 author points out that these banded ironstones are the 

 oldest known auriferous sedimentary rocks in South 

 .Africa, lying between the basement schists and the con- 

 glomerate series, and he considers that on account of 

 what is at present known as to the great width of. the 

 gold-bearing formation, the occurrence of gold in many 

 places in payable quantities, and the amenability of the 

 ores to a simple method of treatment, the exploitation of 

 mines in the series is likely to assume considerable 

 importance in future South African history. 

 Pakis. 

 Academy of Sciences, January 11;. — M. Henri Becqueiel 

 in the chair. — Note on the density of graphite : H. 

 Le Chatelier and S. Wologdine. On account of the 

 wide range of densities which various experimenters have 

 given for graphite, it has been assumed that graphite is 

 not a single variety of carbon, although this is contra- 

 dicted by the constancy of the heat of combustion of 

 purified graphite. The authors have e.\amined the follow- 

 ing : — Acheson graphite (artificial) ; graphite from Ceylon, 

 Australia, Bohemia (Mugrau and Scharzbach), Greenland, 

 commercial graphite, and from cast iron. The method 

 employed was flotation in a heavy liquid (mixtures of 

 acetylene bromide and ether), care being taken to 

 eliminate all air bubbles. The figures for the unpurified 

 material from these sources varied between 1-62 and 2-66. 

 Purification by Moissan's method was then tried, but the 

 results were no more concordant, the deviations being 

 finally traced to the imperfect removal of air. This was 

 surmounted by removing the air by a vacuum, strongly 

 compressing, breaking up again, placing a second time 

 in a vacuum, and re-compressing. Under these experi- 

 mental conditions all the natural and artificial graphites 

 after complete purification gave the same density. of 2-255 

 at 15° C. compared with water at 4° C. — The utilisation 

 of turf for the purification of sewage ; A. Muntz and 

 E. Laine. The experiments detailed show that natural 

 turf is a highly satisfactory medium for forming sewage 

 filter beds. The experimental filter has been at work for 

 more than seven months, and its activity is still un- 

 impaired. It is capable of treating a volume of from three 

 to four cubic metres of sewage per square metre of surface 

 per day. Figures are given of the chemical and bacterial 

 purification effected, and fish live without inconvenience 

 in the effluent. If loaded above this, the effluent is fair, 

 but not so good, and it has been noted that on reducing 

 the load to the normal figure the filter immediately 

 recovers to original efificiency. — Observation of the transit 

 of Mercurv at" the Observatory of Rio de Janeiro : M. 

 Morize. The atmospheric conditions were unfavourable 

 to good observations. — Observation of the transit of 

 Mercurv of November 13-14, 1907, at Schoi, Italv : Fr. 

 Faccin. The atmospheric conditions were bad. — The 

 summability of Fourier's series: A. Buhl.— The choice of 

 the exponent of convergence for integral functions of in- 

 finite order: .'\. Denjoy. — The measurements of general 

 movements of the soil bv means of levellings repeated at 

 long intervals : Ch. Lallemand. An analysis of the 

 degree of exactitude practically possible in levelling opera- 

 tions shows that it is only in exceptional cases that a 

 repetition of the measurements will permit the demonstra- 

 tion with certainty of gradual general movements under 

 I decimetre.— The 'statics of a deformable surface and the 

 dvnamics of a deformable line : Eugene and Francois 

 Cosserat. — The transformations of solutions of white 

 phosphorus into red phosphorus : Albert Colson. Experi- 



