178 



NA TURE 



[April 8, 1909 



tion — including?, not only secondary schools, but also the 

 insrvuction of pupil-teachers — the training of teachers, the 

 provision of scholarships, evening schools or the various 

 lorms of technical instruction, and higher education in 

 science and in art generally. A diagram has been intro- 

 duced into the Blue-book this year showing graphically, 

 for three years, including 1906-7, the comparative rise 

 and fall of certain selected items of expenditure, other 

 than out of loans, of local authorities for classified groups 

 of areas. The income from all sources for meeting the 

 year's expenditure showed a total increase, as compared 

 with the previous year, 1905-6, of nearly 213,000/., and 

 the increased amount raised from rates was equivalent to 

 about 97 per cent, of that total. The total expenditure 

 on higher education, as already defined, was, during the 

 year, 3,680,718/., as compared with 3,355,434/. in the 

 previous year. In 1906-7 the expenditure under various 

 headings was as follows : — for secondary education, 

 1,068,655/. ; for evening schools and institutions for higher 

 and technical education, 1,475,358/. ; for exhibitions, in- 

 cluding scholarships, bursaries, and the payment of fees, 

 448,769/. ; for training of teachers other than pupil- 

 teachers, 98,599/. In addition to these items, adminis- 

 trative and legal expenses accounted for 198,073/., other 

 expenses amounted to 120,320/., and 220,480/. was paid 

 in respect of loans. 



The thirty-sixth annual dinner of the " Old Students " 

 of the Royal School of Mines was held on March 30, under 

 the chairmanship of Mr. F. \V. Rudler, supported by 

 many distinguished guests and old School of Mines men, 

 as well as old students of the Royal College of Chemistry 

 and Royal College of Science. The " Royal School of 

 Mines " was proposed by Sir William H. White, who 

 referred to the admirable record of the school and to the 

 intention of the governing body that its reincarnation 

 should render it second to none in the world. Mr. Rudler, 

 in replying, referred to the early history of the school 

 and to the necessity for combining theory with practice 

 on the lines which had been laid down in drawing up the 

 plans for the new laboratories and testing floors, and 

 expressed the hope that it might be possible to found a 

 chair of economic geology. The toast of " The Visitors," 

 proposed by Mr. Bedford McNeill, was responded to by 

 Mr. A. H. Dyke Acland, who pointed out that " character 

 and grit," as well as the admirable training in the re- 

 organised Royal School of Mines, are essential to a 

 student's success. In concluding, Mr. Acland referred to 

 the proposed students' union building, which he hopes 

 will worthily represent the governors' desire for the bodily 

 and mental welfare of the students, both of the Royal 

 School of Mines and of the other colleges, &c., connected 

 with the Imperial College of Science and Technology. 

 In replying to the toast of "The Chairman," Mr. Rudler 

 referred to the loss sustained by the mining and metal- 

 lurgical professions by the death of Bennett H. 

 Brough. Provision for the widow and children has been 

 made by the Iron and Steel Institute, and it is now pro- 

 posed to invite subscriptions for an entirely different pur- 

 pose, which is for the formation of some permanent 

 memorial to perpetuate the memory of one who was widely 

 honoured and loved. Notices will be sent out shortly with 

 the view of the foundation of a scholarship at the Royal 

 School of Mines. All who knew Brough will agree 

 that such a scholarship is the very thing which he would 

 have desired, and that a more fitting occasion could not 

 have been chosen for this — the first official announcement 

 of what had been in the minds of so many since the death 

 of their old friend. 



SOCIETIES AND ACADEMIES. 

 London, 

 Royal Society, January 21. — "The Phmo-eleclric Fatigue 

 of Zinc. — 11." By H. Stanley Allen. Communicated by 

 Prof. H. A. Wilson, F.R.S. 



In a former paper (Roy. Soc. Proc, A, vol. I.xxviii., 

 P- 483. '907) an account was given of the way in which 

 the photo-electric activity of zinc diminishes when the 

 :nrta! is exposed to light from a Nernst lamp. 



1 he experiments described in the preseiit paper were 

 XO. 2058, VOL. 80] 



carried out to determine whether the results were similar 

 when using a source of light giving far more ultra-violet 

 radiation than the Nernst lamp. A mercury-vapour lamp 

 of fused quartz was employed. 



The method of experimenting was similar to ihat 

 described in the previous paper, but the testing cell, con- 

 sisting of the zinc plate and a positively charged sheet of 

 wire gauze, was in the open air instead of being enclosed 

 in a brass case. 



Conclusion. — The photo-electric activity of a zinc plate 

 dccaj's in such a way that it can be represented as the 

 sum of two exponential terms. The constants of change 

 are but little altered by considerable variations in the 

 character and intensity of the illumination employed, 

 though the value of the photo-electric current is changed 

 considerably. The rate at which the surface is altered is 

 not greatly affected by using a mercury-vapour lamp in 

 place of a Nernst lamp. 



Royal Microscopical Society, March 17. — Mr. E. I. 

 Spitta, vice-president, in the chair. — The optical examina- 

 tion of a crystal section in a rock slice : Dr. J. W. Evans. 

 • — Synchaeta fennica, sp.n., and on the resting-egg of 

 5. pectinata : C. F. Rousselet. 



Mineralogical Society, March 23. — Principal H. A. 

 .Miers, F.R.S., prusident, in the chair. — A stage gonio- 

 meter for use with the Dick pattern of microscope : Prof. 

 H. L. Bowman. The form of goniometer, intended to 

 be screwed to the stage of a microscope w'ith rotating 

 Nicols, which was designed by Principal Miers, has been 

 slightly modified by the author with the view of securing 

 increased rigidity and ease of control. The instrument is 

 adapted for supporting and manipulating a small crystal 

 during the examination of etching-figures or other features 

 requiring high magnification, as well as for the deter- 

 mination of its optic axial angle in air or oil, and the 

 extinction angles and other optical characters of the various 

 faces. It is provided with screw motions for adjusting and' 

 centring the crystal, and for regulating the height of the 

 axis above the stage. — The electrostatic separation of 

 minerals ; T. Cook. Conductivity is a much more 

 important factor than specific gravity in determining the 

 behaviour of mineral fragments under the influence of an 

 electrostatic charge. The greater susceptibility of good 

 conductors as .compared with bad conductors can be made 

 still more pronounced by providing for the escape of the 

 repelled opposite charge, which takes place rapidly in 

 good conductors and slowly in bad conductors. It was 

 shown that, in consequence of this fact, grains of such 

 good conductors as ilmenite, pyrites, galena, or wolfram 

 can be easily separated by means of a rubbed piece of 

 sealing-wax from admixed grains of bad conductors, such 

 as calcite, quartz, fluor, or monazite. Minerals having a 

 metallic lu.^tre are good conductors, whereas those which 

 are colourless and highly transparent are bad conductors. 

 It is suggested that there is probably a much closer con- 

 nection between the conductivity of a mineral and its 

 general optical properties than has been hitherto suspected. 

 — The identity of guarinite and hiortdahlite : Dr. F. 

 Zambonini, with chemical analysis by Dr. G. T. Prior. 

 The rare mineral guarinite, which occurs sparingly in 

 small yellow crystals in the sanidinite bombs of Monte 

 Sonima, has been hitherto regarded as orthorhombic, and 

 as essentially a complex silicate of lime, alumina, and 

 soda. A new investigation made by the author on crystals 

 showing terminal faces shows that the mineral is really 

 Iriclinic, and identical both crystallographically and 

 optically with hiortdahlite. Crystals of guarinite show 

 polysynthetic twin lamellfe with oblique extinctions like 

 those exhibited by crystals of hiortdahlite. The chemical 

 rmalysis showed that the mineral is essentially a fluo- 

 silicate and zirconate of lime and soda, practically identical 

 in composition with hiortdahlite, although the percentage 

 of fluorine was lower than that given in Cleve's analysis 

 of the latter mineral. The numbers obtained in the ; 

 analysis correspond closely to a formula 



3CaSiO,.Ca(OH,F)Na.ZrO,. 

 — Note to a paper on the comparison of refractive indices i 

 of minerals in thin sections: Dr. J. W. Evans. Parallel! 

 Nicols are placed so as to bisect the angle between the, 



