October 7, 19 15] 



NATURE 



159 



the relations which ought to exist between the local 

 museum and the national museum. Difficulties arose 

 w hen it was required to determine in particular cases 

 what objects were of national importance and should 

 be preserved in a national museum. 



After the first function of a local museum had been 

 dequately discharged, Dr. Hoyle thought that if 

 aeans and opportunities allowed, collections should be 

 provided which gave the visitor a preliminary sketch 

 of some department of knowledge. He alluded to 

 "index" collections, though he thought the term 

 ■introductory" collections would be more appropriate. 

 Dr. Hoyle had something to say with regard to the 

 coming into touch of the museum with the educational 

 system of the locality, and he saw nothing out of 

 place in a local museum developing a special subject 

 quite disconnected with the locality if it had the power 

 to do so without interfering with its proper work. 



In the discussion which followed, Dr. Bather 

 touched upon principles which should guide local 

 curators in their selection of what should be considered 

 of national and local interest. Type specimens should 

 be placed in museums where they would be w^ell 

 looked after. Moreover, researchers, though they 

 would naturally seek for local objects, such as fossils, 

 in a local museum, ought not to have to look for, 

 say. New Zealand fossils, through all the museums oif 

 the British Isles. 



Dr. Marie C. Stopes thought that there might be a 

 balance of good in decentralising collections, even of 

 type specimens, for the visiting of local museums 

 brings a stimulus to the local people, and widens and 

 humanises the interests of specialists. 



It seemed evident from other remarks that if local 

 museums are to be properly educational, in the general 

 sense of the word, there should be sp)ecial institutions 

 or special sections of existing museums with their 

 own organisation, so as not to burden curators unduly. 



Prof. Geddes directed attention to the survey of 

 Greater London now being carried out by the Archi- 

 tects' War Committee, which deserved the co-opera- 

 tion of museums and natural history societies. 



The second meeting was held on Friday, Sep- 

 tember 10. As a result of the importance of the 

 presidential address, and the interest which had been 

 taken in its suggestions, the vice-president, Mr. 

 William Whitaker, moved a resolution in the follow- 

 ing terms: — "That this conference invites the atten- 

 tion of the Corresponding Societies' Committee to the 

 president's opening address, in which suggestions are 

 made for reforming the existing, varied, and un- 

 organised practice of publishing original papers." 

 An outline was given of ways in which this might be 

 done, and the resolution was carried. 



The second subject foi discussion was "Colour 

 Standards," suggested by the British Mycological 

 Society, and introduced bv Mr. J. Ramsbottom. He 

 described and illustrated a number of the schemes 

 which had been formulated wi.h the object of obtain- 

 ing some uniformity of colour description in the many 

 branches of natural science. Recent attempts at 

 colour standards have each something against their 

 general adoption, and, except for horticulturists, 

 mycologists, and possibly ornithologists, they are 

 much too full. It would seem best to have a well- 

 arranged list of two hundred well-named colours for 

 ordinary use, which colour scheme could be amplified 

 in those branches of science where needed. 



In this case, also, a good discussion was aroused, 

 and as it was pointed out that the work of preparing 

 such a series of colour standards for scientific and 

 commercial uses, though of interest to many of the 

 committees of the Association, was not the province 

 of any one of them, a resolution was passed referring 



NO. 2397, VOL. 96] 



the matter to the Corresponding Societies' Com- 

 mittee. 



In many ways the Conference of Delegates at Man- 

 chester was the most successful that had been held in 

 this country for a considerable time. 



Wilfred Mark Webb. 



SECTION B. 



CHEMISTRY. 



Opening Address ' by Prof. William A. Bone, 

 D.Sc, F.R.S., President of the Section. 



This year is, as many of you are doubtless aware, 

 the centenary of Davy's invention of the miner's 

 safety lamp which formed the starting point of his 

 brilliant researches upon flame, in which he disclosed, 

 and brought within the range of experimental inquiry-, 

 most of the intricate and baffling problems connected 

 with the fascinating subject of gaseous combustion. 

 Also the ground on which we meet to-day is known 

 to the whole scientific world as the place where, 

 during more than a quarter of a century of continuous 

 investigation, a succession of Manchester chemists, 

 led and inspired by Prof. H. B. Dixon, have devoted 

 themselves to the elucidation of the many problems 

 which Davy's work foreshadowed. Therefore, both 

 in point of time and place, the occasion is singularly 

 appropriate for a review of recent advances in this 

 important field of scientific inquiry. 



At the Sheffield meeting of the Association in 1910, 

 I had the honour of presenting to a joint conference 

 of Sections A and B (Physics and Chemistry) a re- 

 port summarising the then "State of Science in 

 Gaseous Combustion," ^ which gave rise to a keen 

 and stimulating discussion, and was not only printed 

 in extenso in the annual reports for that year, but 

 was also widely circulated through the medium of 

 the scientific and technical Press. There is no need, 

 therefore, for me to refer in any detail to the results 

 of researches already dealt with in that report. I can 

 more usefully devote part of the time at my disposal 

 to supplementing it with a review of more recent re- 

 searches, which have considerably extended our know- 

 ledge in many directions. 



Gaseous Combustion : Ignition Phenomena. 



The first section of my 1910 report was concerned 

 with ignition temperatures .md the initial phases of 

 gaseous explosions ; and it is in connection with 

 ignition phenomena that subsequent progress has been 

 most marked. 



For the ignition of a given explosive mixture, it is 

 necessary that the temperature of its constituents 

 should be raised, at least locally, to a degree at which 

 a mass of gas self-heats itself by combination until it 

 bursts into flame, or, in other words, to a degree at 

 which the chemical action becomes autogenous or 

 self-propelling, so that it quickly spreads throughout 

 the whole mass. This particular degree, or in some 

 cases range, of temperature is commonly spoken of as 

 the ignition-point of the mixture; but in using the 

 expression, certain qualifications should be carefully 

 borne in mind. In the first place, as H. B. Dixon 

 and H. F. Coward showed in 1909,* whereas when 

 certain combustible gases — such, for example, as 

 hydrogen and carbon monoxide, th« mechanism of the 

 combustion of which is probably of a fairly simple 

 character — and air or oxygen are separately heated in 

 a suitable enclosure before being allowed to mix. tlu 

 temperature at which ignition occurs lies witliin a 



1 AbriHjjed by the author. 



2 Sfc /cumal n/Gas Lighting, vol. cxi.. p. 648. 

 j ' /A»rf., vol. evil., p. 323. 



