NA TURE 



[May 5, 1904 



values of these. We may take therefore these values as 

 the characteristics of the different substances. How many 

 of such characteristics exist I cannot tell. Only for 

 simplicity's sake I will assume that two of them are 

 sufficient. As I will take care not to deduce any con- 

 clusions from this number, we shall not be led into error 

 by accepting it. 



We place these two characteristics in a system of planar 

 coordinates ; then the several elements will be represented 

 by single points in the plane. We lay the plane horizontally 

 and raise from these points ordinates, representing the 

 available energy of each element. Between the points of 

 the elements in the plane are situated the points of all 

 possible solutions, filling up the whole plane. Each of 

 these solutions will also have its available energy, and all 

 the corresponding points in space will form a continuous 

 surface. The form of this surface can be described in a 

 general way. For as each element has its point in a relative 

 nii)timiim, the surface as a whole will have a shape like 

 the ceiling of a cavern full of hanging stalactites, the end 

 of each stalactite representing an element. 



How can we pass from one element to another? 

 Evidently not otherwise than by going over the higher 

 parts of the surface, or the passes separating each stalactite 

 from its neighbours. This can only be done by accumu- 

 lating an appropriate amount of available energy in the 

 element to be changed. Now the concentration of energy 

 is a task we cannot accomplish ad libitum, for the possi- 

 bility very soon ends. Think, for e.xample, of compressing 

 a gas into a given space. Up to some ten thousand atmo- 

 spheres the work of compression will go on smoothly, but 

 after that every metal begins to flow like a liquid, and you 

 cannot proceed further. With the concentration of electric 

 or any other energy the task is similar, and so we come 

 to the conclusion that the concentration of energy can be 

 pushed to only a very limited extent. The application of 

 this result to our question about elements is simple enough : 

 we cannot get over the pass between two stalactites because 

 we cannot attain the necessary concentration of energy. 



From the history of science we learn that these consider- 

 ations contain at least some truth, for the isolation of the 

 elements has ever been dependent upon the power of con- 

 centrating energy available at that time. The most brilliant 

 example is the application of the voltaic pile to the isolation 

 of the alkali metals by Humphry Davy. 



Still I must confess that these last considerations are in 

 a very embryonic state, and I should not have brought 

 them before you if an unexpected application had not lately 

 made itself manifest. Some years ago I explained these 

 views to my old friend Sir William Ramsay, when he asked 

 me how the idea of elements fitted into my conceptions of 

 energy. Then I forgot all about it until Sir William re- 

 mmded me of it, saying that his perplexing discovery of 

 the transmutation of radium into helium might conceivably 

 find some explanation in this way. This I am convinced 

 of, and the considerations may be' pictured in the following 

 manner. 



In the corner of our cavern where the elements with the 

 highest combining weight are assembled, the stalactites 

 are very short; and at last they are not really stalactites, 

 but rather regions of different slope in the sloping ceiling! 

 Where the plane is nearly horizontal a drop of water 

 furnishes a picture of the stability of the elements. While 

 hanging at the end of a true stalactite, more or less work 

 must be done to raise the drop over the pass until it flows 

 down another stalactite. But in this corner it will flow 

 of Its own accord, and only delav for a short time on the 

 nearly horizontal portions in the ceiling. 



Such elements will have only a temporary existence 

 Now we are sure that for the transmutation of one element 

 into another enormous amounts of energy would be re- 

 quired, for the concentrations of energy as yet available 

 have proved themselves insufficient for this purpose. We 

 may expect, therefore, that enormous amounts of ener^^y 

 will be liberated if such an unstable element changes into^a 

 stable one. This accounts for the extraordinary quantity 

 of energy developed by radium during its existence The 

 fact that radium changes into helium, an element with an 

 exceptionally long stalactite (for it is impossible to get even 

 any combination of helium), makes us expect indeed such 

 NO. 1801, VOL. 70] 



an unusually great development of energy as is found to 

 occur.' 



The heat from radium is surely only the last form of the 

 energy developed in its transformation. There are a great 

 many intermediate forms, termed rays or radiations, which 

 have been studied by a band of eminent workers, whose 

 ingenuity and ability have been displayed in the most 

 brilliant way during these investigations. Perhaps I may 

 venture the suggestion that first, other intermediate 

 temporary elements are formed, and that the energy liber- 

 ated at this transmutation appears first in the shape of 

 new, still imperfectly known forms. It is most likely that 

 such forms are originated during the decay of the enor- 

 mously concentrated energy of radium ; at the same time 

 it is probable that we have not yet the means of fixing 

 these forms and so preventing their changing into other 

 more common forms. We should remember that, for 

 example, the conservation of electric energy at a pressure- 

 of some thousand volts during some months or years is by 

 no means an easy thing, and I have great doubt if it is 

 possible at all. 



But here I must conclude, for I have ventured to intrude- 

 on a field where I have not secured my own right of entry 

 by personal work. I see among my audience men who are- 

 possessed of an incomparably more minute and compre- 

 hensive knovi'Iedge of these new realms of science than I. 

 I must ask you, therefore, to take these suggestions in the 

 same spirit as that in which Faraday took his own specu- 

 lations. They are questions put to nature. If she says. 

 Yes, then we may follow the same path a little further. 

 If she says No — well, then we must try another path. 



A SMITHSONIAN MAGAZINE OF SCIENCE. 



"T^O provide a medium for the early publication of the 

 results of researches conducted under the auspices of 

 the Smithsonian Institution, and especially for the publi- 

 cation of reports of a preliminary nature, a quarterly issue 

 of the Smithsonian Miscellaneous Collections has been com- 

 menced. This new periodical has the form of an attractive 

 magazine, and contains papers on a variety of subjects of 

 scientific interest, most of them beautifully illustrated. 



The number opens with a description of seventy new- 

 Malayan mammals, by Mr. Gerrit S. Miller, jun., based 

 on collections made and presented to the U.S. National 

 Museum by Dr. W. L. .\bbott. Mr. C. G. Abbot presents 

 the results of recent studies of the solar constant of radi- 

 ation, conducted at the Astrophysical Observatory of the- 

 Smithsonian Institution, under the direction of Dr. S. P. 

 Langley. Another paper by Mr. Abbot describes the new 

 ccelostat and horizontal telescope of the Astrophysical 

 Observatory, in which are given the results obtained with 

 a device designed by Dr. Langley for the purpose of 

 " churning " a column of air traversed by a solar beam, 

 with the view of reducing the " boiling " or confusion of 

 all parts of the solar image due to variability of the strata 

 of air traversed. Dr. F. W. True presents some photo- 

 graphic illustrations of living finback whales from New- 

 foundland, these being the first photographs of living whales- 

 in American waters that have thus far been published. 

 Brief descriptions of a skeleton of Hesperornis, and a new 

 Plesiosaur, by Mr. Frederic A. Lucas, are given with plates, 

 and Mr. W. H. Holmes illustrates and compares the designs 

 on some remarkable shell ornaments from Kentucky and 

 Mexico. 



A noteworthy specimen of a Glacial pothole in the 

 National Museum is described by Mr. George P. Merrill, 

 who explains the method by which the specimen was pro- 

 cured. Some notes on the herons of the district of 

 Columbia, by Mr. Paul Bartsch, who made a systematic 

 survey of two heron colonies and conducted experiments 

 with the view of solving some of the problems of bird life, 

 are of special interest. Dr. J. Walter Fewkes gives a pre- 

 liminary report on an archasological trip to the West Indies 



} Compare Soddy, "The Wilde Lecture," Mem. and Prac. Manchester 

 Lit. and Phil. Soc. 1904. I am very glad to find that I am in close agree- 

 ment (e,\cept in so far as there is a difference in his accepting the atomistic,, 

 while I hold by the energetic point of view) with this most zealous and 

 fortunate worker ; indeed, the above statements were written and printed. 



before 1 saw Mr. Soddy's lectu 



