Sept. 8, 1887] 



NATURE 



443 



pni 



memoirs by eminent chemists containing not a sin^jle quantitative 

 determination. Strange as it may seem, two able chemists, 

 Boettger and Schoenbein, were living until quite recently who 

 worked and obtained valuable results without resorting to the 

 balance, the instrument which of all others seems the most in- 

 dispensable to the chemist of to-day. The balance was indeed 

 universally employed in my younger days, but no other instru- 

 ment, properly so called, was ever seen in the laboratory. The 

 spectroscope was not yet invented; the polariscope had not come 

 into use ; volumetric analysis was still in its infancy. Even the 

 thermometer was but seldom used. What a different picture 

 does the laboratory of the present day present, with its instru- 

 ments of precision and its various appliances for effecting 

 quantitative determinations of all kinds ! 



Whether the universal prevalence of, and exclusive attention 

 to, quantitative methods in chemistry has been an unmixed good 

 may be doubted. Who has not run with a weary eye over the 

 long array of figures, the never-ending tables of which some 

 modern memoirs seem to consist, and not longed for some mere 

 description — were it only regarding trivial matters — to relieve 

 the monotony and fix the subject treated of on the memory ? 

 That quantitative determinations given in quite precise terms 

 may occasionally be entirely futile may be seen on referring to 

 the history of alchemy. One of the later alchemists professes to 

 have converted 5400 parts by weight of copper into 6552 parts 

 of silver by the action of i part of a metal-improving substance — 

 philosopher's stone (Kopp, "Die Alchemic"). Here we see 

 " ;e quantitative method applied to a purely chimerical process, 

 borated from the depths of the experimenter's inner conscious- 

 s, and of no value whatever. Much of what is at the present 

 day carefully worked out and presented to the world in numerical 

 form may, like this statement of the alchemist, pass away and 

 be forgotten. This may possibly be the case with the numerous 

 carefully-made analyses of water which we now meet with, and 

 which we would gladly exchange for a few decided qualitative 

 tests of its hygienic properties. In the case of air and water it 

 is not the minuteness of the noxious matter which causes doubts 

 to arise, but the absence of any decided and undoubted chemical 

 characteristics of the impurities present. It is probable that a re- 

 fined sense of taste, uncorrupted by the luxurious indulgences 

 which civilization has introduced, would be able to detect differ- 

 ences in drinking-water which might escape the attention of the 

 most consummate analyst. 



Whatever objections may, however, be entertained to the 

 application of quantitative methods in natural science, to the 

 exclusion of others, it is certain that important results have 

 flowed from their adoption, insomuch that we seem to have 

 arrived at the conclusion that the expression of quantitative 

 results is the be-all and end-all of science ; that all differences 

 are merely quantitative ; that there is no such thing as mere 

 quality. The whole philosophy of our age is expressed in this 

 one proposition : All differences within the sphere of our experi- 

 ence are quantitative. It is the basis of Darwinism, if I am not 

 mistaken, and underlies many of our political and social 

 theories. Of course it is a mere assumption if slated generally, 

 for the phenomena that admit of purely quantitative expression 

 are few in number compared with those that do not ; but then it 

 is surmised, and with some degree of probability, that the vast 

 region outside the quantitative sphere will in time come to be 

 included within it. The past history of science seems to render 

 this likely in the future. The science of chemistry has so far, 

 however, pre-ented an insuperable barrier to the general adop- 

 tion of this view, and will continue to do so as long as the so- 

 called elements remain what we now admit them to be — inde- 

 structible, immutable, inconvertible. It is possible to denote 

 all the known properties of gold and silver, their atomic weight, 

 specific gravity, hardness, malleability, action towards heat, light, 

 and electricity, in precise numbers with reference in each case to a 

 certain standard ; and yet we cannot say that silver minus a little of 

 this, plus a little of that, constitutes gold — the two elements are 

 essentially and radically distinct. Unless we admit with the 

 alchemists that by taking away a little of A and adding a little 

 of B we can convert one metal into another, one element into 

 another, the quantitative method must fall short of its complete 

 development in chemistry. Numerous attempts have, there- 

 fore, been made to show the theoretical probability, even if it 

 should not be possible to prove it experimentally, of the so- 

 called elenients being really compound bodies, or at least of 

 their containing a basic matter common to all. My predecessor 

 in this chair has endeavoured to show, in the brilliant address 



delivered to this Section on the occasion of its last meeting, that 

 the barrier hitherto presented to us by the intractability of our 

 present elements may be overcome, and has adduced experi- 

 mental illustrations in favour of his views of the compound 

 nature of the elements, Mr. Crookes has called to his aid the 

 doctrine of evolution, which has proved so valuable an instru- 

 ment in the hands of the biologist, maintaining that the elements, 

 like the species of plants and animals, were gradually evolved 

 by some process of condensation from a primordial matter called 

 by him protyle, each step in the process being repre>ented by a 

 distinct element. This is doubtless taking very safe ground, for 

 if the process of evolution was the same in the inorganic as it 

 is supposed to have been in the organic world, the process can 

 never be repeated, and we shall, therefore, never be in a position 

 to illustrate it experimentally. I may, however, have misunder- 

 stood what Mr. Crookes meant to convey, antt, if so, must apolo- 

 gize for the dulness of my apprehension. Granting, however, 

 the possibility of our resolving our present elements, were it in 

 theory only, into modifications of one basic material out of 

 which they have been evolved, the question would still remain 

 to be answered, What has caused this primordial matter to be 

 split up into groups and forms having distinct and opposite 

 qualities? and when this question is answered, if it can be 

 answered even in a problematical way, then o.her questions 

 would arise, until by degrees we should arrive at the 

 confines of physical knowledge and find ourselves in the 

 region of metaphysics, where scientific reasoning ceases, and 

 thinking for scientific purposes becomes unprofitable. Ex- 

 cursions into this region would indeed be very useful if on 

 returning to physical regions we could every time bring back 

 with us an instrument as potent and far-reaching as the atomic 

 theory has proved to be, a theory which still remains the basis 

 of all our reasoning in chemistry ; but then the atomic theory has 

 been quite an exceptional instance. Metaphysical speculation, 

 such as the Naturphilosophie of the Germans has dealt in, has, 

 generally speaking, been utterly barren in natural science. 



I will not on the present occasion dwell on the vast addition 

 made to the number of useful and beautiful substances by 

 chemists during the last fifty years. Their number is legion, 

 and their mere description fills volumes, whereas half a century 

 ago a dictionary of moderate size would have sufficed for the 

 purpose. Among these newly-discovered substances none are 

 more remarkable than the metals rubidium, cEesium, thallium, 

 indium, gallium, the existence of which was revealed by the 

 spectroscope, and which, indeed, would have probably remained 

 unknown but for the labours of Bunsen and Kirchoffin perfecting 

 and applying that instrument. 



I must not, however, omit all reference to a department of 

 chemistry which has been, one may almost say, created within 

 the time to which I am referring — I mean that of synthesis. 

 When I began to study chemistry we only heard of analysis ; 

 of synthesis, so far at least as regards organic bodies, we only 

 dreamt as a remote and unattainable region. The only instance 

 then known of the synthesis of an organic substance was that of 

 urea by Wohler. Synthesis was, indeed, supposed to be an 

 essentially vital process effected under the influence of the vital 

 force, and quite outside the sphere of the chemist. Since then 

 what marvels have we not seen ? Alizarin and purpurin, the 

 colouring-matters of madder, have been prepared artificially by 

 Graebe and Liebermann, indigo by Baeyer, not to mention 

 bodies of simpler constitution obtained by comparatively less 

 complicated processes. We are honoured to-day by the presence 

 of Prof. Ladenburg, who has succeeded in artificially preparing 

 coniin, the alkaloid to which hemlock owes its poisonous proper- 

 ties ; the first natural alkaloid, indeed, which has been obtained 

 artificially. Looking back at what has been achieved, I think 

 we may entertain the confident anticipation that all the most 

 important organic bjdies, acids, alkaloids, and neutral sub- 

 stances will, in course of time, be obtained in a similar manner, 

 though of one thing we may be pretty sure — viz. that we shall 

 never succeed in firming any really organized matter as distinct 

 from organic. The term organic matter is in fact only employed 

 for the sake of convenience, and as an expression handed down 

 to us from former days, since so-called organic compounds are 

 subject to the same laws with regard to composition as the 

 bodies which we name mineral or inorganic, but organized 

 matter such as we find constituting the vessels of plants and 

 animals is a different thing. The protoplasm contained in the 

 vegetable and animal cell is something very distinct from the 

 same matter after the death of the organism, but tht difference 



