NA TURE 



[October 7, 1922 



off and was advancing down the latter and towards 

 it from various points along the river course on the 

 left. 



Owing to the steady progress between June 18 

 and 25, and the rapid flow on the latter date, I 

 considered it advisable to order the removal of all 

 the machinery and the salving so far as possible of 

 all building materials worth removing from machine 

 house, cacao house, hospital, and director's house. 



On July ill again visited Bibundi. The lava had 

 advanced considerably since June 25, but its activity 

 is gradually dying out, though the lava streams from 

 the crater, so far as can be seen in this very misty 

 weather, continue as strong as ever. Probably there 

 will be another period of rest and banking up to be 

 followed by a further advance, and everything points 

 to this following the line of the iron road and Govern- 

 ment road to the cacao store and machine house, 

 and possibly breaking through the main portion of 

 Thormahlenfelde to the Ninonne River higher up. 



On July 15 the manager of Bibundi reported : 

 " The main lava stream is quiet ; but for the last 

 three nights I have seen a large new stream coming 

 down the mountain. It is very bright and much 

 closer to this side than before." 



The Royal Photographic Society's 

 Exhibition. 



T^HE Annual Exhibition of the Royal Photographic 

 J- Society at 35 Russell Square remains open until 

 October 28. Admission is free. The natural history 

 section of the scientific and technical division has 

 improved considerably in recent years. There are 

 still a good many single photographs of an animal, 

 a flower, or an insect that have no particular interest, 

 or if they have it is not indicated ; but there are 

 many series showing progressive changes, such as 

 Dr. S. Hastings's nine illustrations of soil formation 

 in the Alps, in which he shows the bare rock covered 

 at first with crustaceous lichens, and traces the stages 

 of vegetation until an alpine meadow is produced. 

 Other series show many varieties of the same kind of 

 thing, as Mr. C. H. Caffyn's thirty sections of cal- 

 careous, arenaceous, and igneous rocks, and Dr. 

 Rodman's animal and vegetable hairs. With scarcely 

 any exception the photography in this section is 

 excellent. 



Among the " Technical Applications of Photo- 

 graphy " Dr. J. S. Plaskett shows four photographs 

 taken at the focus of the 72-inch reflecting telescope 

 at the Dominion Astrophysical Observatory, Victoria, 

 B.C., which also give evidence of the accuracv of 

 figure of the mirror. The Mount Wilson Observatory, 

 Carnegie Institution of Washington, contributes 

 specimens of the work of the 100-inch Hooker reflector 

 and of the 60-inch reflector, as well as photographs 

 of the unusual spectra of seven stars, made with these 

 instruments. Enlarged negative prints of a latitude 

 variation plate and a wave-length plate are among 

 the exhibits of the Astronomer Royal, Greenwich. 



The production of accurate comparative scales by 

 photographic means is fully described and illustrated 

 by Mr. A. E. Bawtree, and Mr. Wilfred Mark Webb 

 shows how, by chemical and photographic means, a 

 Russian internal passport was made to yield deleted 

 details which showed that the document had done 

 duty on four separate occasions for as many different 

 persons. 



Mr. G. A. Clarke illustrates upper cloud formations 

 which support the theory of Prof. Bjerknes that 

 depressions have their origin in the meeting of a 



warm, moist, equatorial current and a cold, dry, 

 polar current. Cloud formation and structure is 

 shown from the upper side by Mr. F. W. Baker. 



There are many exhibits that deal with the techni- 

 calities of gelatine plate manufacture and the statisti- 

 cal properties of plates by workers in America, as 

 well as in this country. We may refer specially to 

 the beautiful photomicrographs of silver bromide 

 crystals, at 3000 diameters, by Mr. A. P. H. Trivelli, 

 and the characteristic curves of modern high-speed 

 dry plates with photomicrographs of the grains that 

 constitute the sensitive material by Mr. J. W. Grundy. 

 Mr. Grundy also contributes a fine series of photo- 

 graphs taken under various conditions from a height 

 of about 14,000 feet. 



Among numerous radiographs by several workers 

 the effect of the Potter-Bucky diaphragm is shown 

 by Mr. R. B. Wilsey. This diaphragm consists of a 

 grid made of parallel strips of lead foil, the planes of 

 which are in line with the direction of the radiation 

 from the tube. It is placed between the patient and 

 the film, and moved during the exposure so that it 

 may not show on the radiograph ; it absorbs a large 

 proportion of the scattered rays. 



There is a large collection of colour transparencies, 

 and among them some of scientific interest, but the 

 most remarkable are the stereoscopic slides made on 

 autochrome plates by Mr. S. Pegler. The successful 

 reproduction of the colour and the brilliancy of silver 

 plate, various articles of jewellery, and coloured 

 stones, together with the realistic appearance, 

 demonstrates possibilities of this method that are 

 little known. C. J. 



University and Educational Intelligence. 



London. — The senate of the university includes 

 sixteen members elected by registered members of 

 convocation and sixteen by the faculties. Of the 

 former, six are elected by the registered graduates in 

 science ; and of the latter, the faculty of science 

 appoints four. There are two vacant seats in science, 

 and five candidates have presented themselves as 

 candidates for them. The candidates are : Dr. 

 George Senter, principal of Birkbeck College, and 

 author of a number of papers and other works on 

 chemistry (Dr. Senter is a member of the faculty of 

 science, and is therefore eligible for election as a 

 representative of the faculty in the senate) ; Mr. 

 T. LI. Humberstone, an old student and associate of 

 the Royal College of Science, well known to be 

 particularly familiar with the work of the University 

 and educational problems generally ," Dr. Jessie 

 White, who is especially interested in methods of 

 teaching science ; Dr. J. S. Bridges, director of 

 education, Willesden ; and Mr. C. W. Crook, head- 

 master, Central Secondary School, Wood Green. The 

 poll closes on Tuesday next, Oct. 10, and it is hoped 

 that graduates will not fail to send in their voting 

 papers before that date. 



St. Andrews. — The honorary degree of LL.D. was 

 conferred upon the Prince of Wales on September 28. 

 In an address to his Royal Highness after the pre- 

 sentation, Dr. J. C. Irvine, principal of the university, 

 reminded him that St. Andrews was not only a place 

 of beauty and the home of a noble game, but also 

 a centre from which great movements had sprung 

 and powerful influences had spread far and wide. The 

 ancient university was ever ready to enlarge its 

 activities, blending the wisdom of the past with the 

 spirit of progress. 



NO. 2762. VOL. I io] 



