;32 



NATURE 



[February 4, 1892 



has only been rendered possible by photography. If the residual 

 lines common to several elements, and which cannot be traced 

 by this means to any known element, should lead to the dis- 

 covery of new elements or to the resolution of known elements 

 into simpler forms of matter, the credit must be given to the 

 photographic method. 



But it will be safer to confine ourselves to what photography 

 has actually done for science than to attempt to enter the regions 

 of speculation. The case to be made out is such a good one 

 that there is no need to draw upon the imagination. Thus, 

 again in the region of spectroscopy, the relationship between 

 the constitutions of chemical compounds and their power of 

 absorbing certain definite light waves, as investigated by Prof. 

 W. N. Hartley, may be said to have been discovered by means 

 of photography, because the absorption is, in the case of colour- 

 less liquids, exerted beyond the limits of the visible spectrum. 

 In meteorology the photographic plate has also been of the 

 greatest service, and a British Association Committee has been 

 formed for the purpose of stimulating work in this direction. 

 Most of those present are, no doubt, familiar with the more 

 striking results achieved by meteorological photographers. The 

 fleeting forms of clouds can be registered with absolute fidelity, 

 and by an ingenious arrangement of electrically connected 

 cameras the height and rate of motion of clouds has recently 

 been determined by the aid of photography. The character of 

 the electric discharge in the laboratory has been studied photo- 

 graphically by Mr, Shelford Bidwell and by Profs, Oliver 

 Lodge and C. V. Boys, and the large-scale discharge of the 

 lightning flash has been made to impress itself on the photo- 

 graphic plate. The results are known to all ; the conventional 

 zigzag "fork" appears to have no existence in nature. The 

 destructive effects of wind storms on buildings can also be 

 studied in photographs with an amount of accurate detail that 

 it would be impossible to represent by any other method ; and I 

 am informed by Mr. G. J. Symons that important conclusions 

 concerning the nature of the atmospheric movement have been 

 arrived at by the examination of such photographs. 



Passing on to other applications of photography, it is obvious 

 that in geographical and ethnological exploration the camera 

 has become an essential part of the traveller's equipment. In 

 geology again the aid of the photographer has been called in, 

 and with such good results that a British Association Committee 

 has been called into existence, and has been doing excellent 

 work in collecting and registering geological photographs during 

 the last two or three years. In these photographs sections are 

 recorded with a fidelity which it would be impossible to equal 

 except by laborious sketching. Where time is an object, as in 

 the case of sections only temporarily exposed, the camera is 

 invaluable. Moreover, the value of such photographs will 

 increase with time in the same way and for the same reason 

 as photographs of the starry heavens. For while the latter, 

 taken at the time of the present celestial survey, will, by 

 comparison with photographs taken in the far distant future, 

 reveal relative movements among the stars, the geological 

 photographs of the present period will by future comparison 

 with the localities registered fnmish incontestable evidence of 

 the slow course of geological change. 



In biology photography has been utilized with great ad- 

 vantage, and will no doubt become of still greater service in the 

 future. There is no reason why the dry plate, which has al- 

 ready largely superseded the eye in astronomy, should not also 

 relieve the eye of the microscopist. Many biological works 

 have been illustrated with great success by means of photo- 

 micrography, and even in purely systematic works, such, e.g., 

 as Marshall and De Niceville's "Butterflies of India," photo- 

 graphic illustration has been adopted with success. In studying 

 microscopic forms of life, where an evanescent phase of life- 

 history may be full of profound significance, the photographic 

 plate might well replace the eye in those cases where prolonged 

 and fatiguing observation has hitherto been found necessary. 

 The fleeting phases of expression, of such importance in com- 

 parative psychology, have been caught and fixed on the photo- 

 graphic plate with a natural fidelity that it would have been 

 impossible to attain without snch aid, Mr. Darwin's work on 

 "The Expression of the Emotions" was, as you are aware, 

 illustrated by photography even before the dry plate had been 

 worked up to its present exalted degree of sensitiveness. 



The application of photography to the analysis of the move- 

 ments of animals has been made familiar through the remark- 

 able photographs which Mr. Muybridge has on many occasions 



NO. I 162, VOL. 45] 



brought under our notice in this country. Among other resul; 

 recently achieved, I need only refer to those wonderful picture 

 of animals in motion, taken by Messrs. Marey and Anschiitz. 

 Such results as these are not only interesting illustrations of the 

 high state of perfection to which modern photography has been 

 developed, but they are of the highest value in elucidating the 

 mechanism of animal movement, and of the flight of birds. 

 The introduction of photography into this branch of animal 

 mechanics has led to a complete revision of pre-existing con- 

 ventional notions, and the indirect effect of such photographic 

 analysis of the phases of motion on the work of the artist is of 

 an importance that cannot be over-estimated.^ 



In the department of anthropology photography h.as served for 

 the faithful registration of race types, and Mr. Francis Galton's 

 method of composite portraiture is familiar to all. In his recent 

 studies of "finger marks" in »connection with heredity, Mr. 

 Galton has alsoTound it indispensable to work from photographic 

 enlargements. 



This imperfect sketch of the scientific applications of photo- 

 graphy might well be followed by a much more extended list of 

 its achievements in the domain of art. But I do not feel myself 

 justified in taking up more time in telling you what you already 

 know, and there are no doubt many present who are far more 

 competent to deal with this aspect of the subject than I am. I 

 cannot help thinking, however, that it would materially help 

 the cause of technical instruction in the desired direction if some 

 competent authority among you were to draw up a complete 

 statement of the benefits which have accrued to art, both 

 abstract and applied, by the introduction of photographic and 

 photo-mechanical methods. ^ 



To all who are interested in the advancement of art and of 

 science, photograjDhy appeals, therefore, as a branch of technology 

 of the first order of importance ; in saying that it appeals to art 

 and to science for such recognition, it is evident that it appeals 

 to the nation at large. Even to the "pure scientist," who is 

 supi^osed to lose interest in a discovery as soon as it becomes 

 practical, i.e. commercial, this subject appeals for support, for 

 from' the study of the photographic processes themselves many 

 important contributions to physics and chemistry have been 

 made, and still greater results may be expected to follow from 

 the investigations of scientific men in this direction. From its 

 purely practical side the claim of photography to be considered 

 as a branch of technology will receive additional support when 

 it is remembered how many distinct branches of manufacture it 

 draws upon, or has, indeeed, actually called into existence. 

 Consider how it is dependent on the optician for the manufacture 

 of lenses ; consider, again, the special branch of cabinet- 

 making and joinery which it has created in order to supply 

 cameras and other instruments ; remember, also, the boon 

 which photography has conferred upon the chemical manu- 

 facturer by the demand for fine chemicals which it has created. 

 Neither must it be forgotten that a new and by no means 

 unimportant development in the manufacture of paper, gelatine, 

 and albumen has arisen through the introduction of photography. 

 From every point of view, therefore, photography claims lo 

 be placed on the same basis as other branches of technology. 

 The Photographic Society, I am happy to see, fully recognizes this 

 in the recent action which it has taken, and which is expressed 

 in the report of the Affiliation Committee. I consider this an 

 excellent move in the right direction. But it is easy enough for 

 the Society to recognize the technical importance of its own 

 subject ; the difficulty is to move public opinion, and to con- 

 vince the nation that we are behind other countries in this re- 

 spect. The first step is to draw up and circulate widely an 

 account of what is being done for photographic technical in- 

 struction on the Continent. I had intended when first invited 

 to lecture here, to offer some such statement, but I was glad to 

 read in a recent number of your loiirnal that this task had been 

 undertaken by Mr. Warnerke, and I hope that some means will 

 be taken to bring his report under the notice of those interested 

 in technical education. It is clear from what has already been 

 attempted by this Society, and from the opinions which have 

 been expressed on all sides by those whose voices carry the 

 weight of authority, that nothing short of a Photographic 

 Institute will meet the requirements of the case. This I most 



' Prof, till Bois-Reymond deals with this in the address referred to. 

 Some of Prof. Marey's recent resuhs are described in Nature, vol. xlv. 

 p. 228. 



^ Since the above was written Prof. E. du Bois-Reymond's address to the 

 Royal Academy of Sciences of Berlin on the " Relation of Natural Science ta 

 Art," has appeared in Nature, vol. xlv. pp. 200 and 224. 



