284 



NATURE 



[August 31, 1911 



loss by death of many distinguished members. Among 

 these are : — 



Dr. John Beddoe, who served on the Council from 1870 

 to 1S75, has recently died at a ripe old age, after having 

 achieved a world-wide reputation by his magnificent work 

 in the domain of anthropology. 



Sir Rubert Boyce, called away at a comparatively early 

 age in the middle of his work, was for long a colleague of 

 mine at University College, and was one of the staff of 

 the Royal Commission on Sewage Disposal. The service 

 he rendered science in combating tropical diseases is well 

 known. 



Sir Francis Galton died at the beginning of the year at 

 the advanced age of eighty-nine. His influence on science 

 has been characterised by Prof. Karl Pearson in his having 

 maintained the idea that exact quantitative methods could 

 — nay, must — be applied to many branches of science which 

 had been held to be beyond the field of either mathematical 

 or physical treatment. Sir Francis was General Secretary 

 of this Association from 1863 to 1868 ; he was President of 

 Section E in 1862, and again in 1872 ; he was President of 

 Section H in 1885 ; but, although often asked to accept 

 the office of President of the Association, his consent could 

 never be obtained. Galton 's name will always be 

 associated with that of his friend and relative, Charles 

 Darwin, as one of the most eminent and influential of 

 English men of science. 



Prof. Thomas Rupert Jones, also, like Galton, a 

 member of this Association since i860, and in 1891 Presi- 

 dent of tin- Geological Section, died in April last at the 

 advanced age of ninety-one. Like Dr. Beddoe, he was a 

 medical man with wide scientific interests. He became a 

 distinguished geologist, and for many years edited the 

 Quarterly Journal of the Geological Society. 



Prof. Story Maskelyne, at one time a diligent frequenter 

 of our meetings, and a member of the Council from 1874 

 to 1880, was a celebrated mineralogist and crystallographer. 

 He died at the age of eighty-eight. The work which he 

 did in the University of Oxford and at the British Museum 

 is well known. In his later life he entered Parliament. 



Dr. Johnstone Stoney, President of Section A in 1897, 

 died on July 1, in his eighty-sixth year. He was one of 

 the originators of the modern view of the nature of elec- 

 tricity, having given the name " electron " to its unit as 

 far back as 1874. His investigations dealt with spectro- 

 scopy and allied subjects, and his philosophic mind led 

 him to publish a scheme of ontology which, I venture to 

 think, must be acknowledged to be the most important 

 work which has ever been done on that difficult subject. 



Among our corresponding members we have lost Prof. 

 Bohr, of Copenhagen ; Prof. Bruhl, of Heidelberg ; Hofrat 

 Dr. Caro, of Berlin ; Prof. Fittig, of Strassburg ; and 

 Prof, van 't Hoff, of Berlin. I cannot omit to mention 

 that veteran of science Prof. Cannizzaro, of Rome, whose 

 work in the middle of last century placed chemical science 

 on the firm basis which it now occupies. 



I knew all these men, some of them intimately ; and, if 

 I have not ventured on remarks as to their personal quali- 

 ties, it is because it may be said of all of them that they 

 fought a good fight and maintained the faith that only 

 by patient and unceasing scientific work is human progress 

 to be hoped for. 



It has been the usual custom of my predecessors in 

 office either to give a summary ol tli> progress of science 

 within the past year or to attempt to present in intelligible 

 ime aspect of the science in which they have 

 themselves been engaged. I possrss no qualifications for 

 the formei course, and 1 therefon ask you to bear with 

 oi' while 1 devote some minutes to the consideration of 

 1 and modern views regarding the chemical elements. 

 To many in my audience part of my story will prove an 



oft-told tale; but I must asli those to excuse me, ii lei 



that it may be in some wis,' complete. 



In tlii- days of the early Greeks the word "element" 

 was p 1,1 denote a property of mailer than 



oni- . . r iis constituents. Tims, when a substance was said 

 to contain fire, air, water, and earth (of which ten 

 childish t^ .• 1 1 1 1 ■ ■ doubtless once played by all of us is a relic), 

 it prof, al.lv m, -ant that they partook of the nature of the 

 so-called elements. Inflammability showed tin presence of 

 NO. 2183. VOL. 87] 



concealed fire ; the escape of " airs " when some sub- 

 si ances are heated or when vegetable or animal matter is 

 distilled no doubt led to the idea that these airs were 

 imprisoned in the matters from which they escaped ; hard- 

 ness and permanence were ascribed to the presence of 

 earth, while liquidity and fusibility were properties con- 

 veyed by the presence of concealed water. At a later date 

 the " Spagyrics " added three " hypostatical principles " 

 to the quadrilateral; these were "salt," "sulphur," and 

 " mercury." The first conveyed solubility, and fixedness 

 in fire ; the second, inflammability ; and the third, the 

 power which some substances manifest of producing a 

 liquid, generally termed " phlegm," on application of 

 heat, or of themselves being converted into the liquid 

 state by fusion. 



It was Robert Boyle, in his "Skeptical Chymist," who 

 first controverted these ancient and mediaeval notion-, ai 

 who gave to the word " element " the meaning that it now 

 possesses — the constituent of a compound. But in thi 

 middle of the seventeenth century chemistry had not 

 advanced far enough to make his definition useful, for he 

 was unable to suggest any particular substance as 

 elementary. And, indeed, the main tenet of the doctrine 

 of " phlogiston," promulgated by Stahl in the eighteenth 

 century, and widely accepted, was that all bodies capable 

 of burning or of being converted into a " calx," or earthy 

 powder, did so in virtue of the escape of a subtle fluid 

 from their pores ; this fluid could be restored to the 

 " calces " by heating them with other substances rich in 

 phlogiston, such as charcoal, oil, flour, and the like. 

 Stahl, however false his theory, had at least the merit of 

 having constructed a reversible chemical equation : — 

 Metal-phlogiston = Calx ; Calx-f- phlogiston = Metal. 



It is difficult to say when the first element was known 

 to be an element. After Lavoisier's overthrow of the 

 phlogistic hypothesis, the part played by oxygen, then 

 recently discovered by Priestley and Scheele, came 

 prominently forward. Loss of phlogiston was identified 

 with oxidation ; gain of phlogiston with loss of oxygen. 

 The scheme of nomenclature (" Methode de Nomenclature 

 chimique "), published by Lavoisier in conjunction with 

 Guyton de Morveau, Berthollet, and Fourcroy, created a 

 system of chemistry out of a wilderness of isolated facts 

 and descriptions. Shortly after, in 1789, Lavoisier pub- 

 lished his " Traite 1 de Chimie," and in the preface the 

 words occur : "If we mean by ' elements ' the simple 

 and indivisible molecules of which bodies consist, it is 

 probable that we do not know them ; if, on the other 

 hand, we mean the last term in analysis, then every sub- 

 stance which we have not been able to decompose is for 

 us an element ; not that we can be certain that bodies 

 which we regard as simple are not themselves composed of 

 two or even a larger number of elements, but because 

 these elements can never be separated, or rather, because 

 we have no means of separating them, they act, so far as 

 we can judge, as elements ; and we cannot call them 

 ' simple ' until experiment and observation shall have 

 furnished a proof that they are so." 



The close connection between " crocus of Mars " and 

 metallic iron, the former named by Lavoisier " oxyde de 

 fer, " and similar relations between metals and their oxides, 

 made it likely that bodies which reacted as oxides in dissolv- 

 ing in acids and forming salts must also possess a metallic 

 substratum. In October, 1807, Sir Humphry Davy proved 

 the correctness of this view for soda and potash by his 

 famous experiment of splitting these bodies by a powerful 

 electric current into oxygen and hydrogen, on the one hand, 

 and the metals sodium and potassium on the other. 

 Calcium, barium, strontium, and magnesium were added 

 to the list as constituents of the oxides, lime, barytes, 

 strontia, and magnesia. Some years later Schi 

 " dephlogisticated marine acid," obtained by heating 

 pyrolusite with "spirit of salt," was identified by Davy 

 as in all likelihood elementary. His words are : " All the 

 conclusions which I have ventured to make respecting the 

 undecompounded nature of oxymuriatic gas are. I con- 

 ceive, entirely confirmed by these new facts." "It has 

 been judged mosl proper to suggest a nam' founded upon 

 one of if- obvious oil characteristic properties, its colour, 

 and to call it chlorine." Tin' subsequent discovery of 



