2l8 



NATURE 



[November 6. 19 19 



quantitative basis. It consummated a change 

 which Cavendish may be said to have originated. 

 It can be proved that Cavendish was cognisant 

 of the principles underlying what we term the 

 "law of constant proportion" and the "law of 

 reciprocal proportion " ; that he foresaw that the 

 facts embodied in these laws are at the founda- 

 tion of all quantitative analytical work, and that 

 in his practice he implicitly recognised their truth. 

 In spite of the widespread political and social 

 disturbance which marked the early years of the 

 last century, a tide in the affairs of chemistry 

 then set in, which, with periods of ebb and flow, 

 reached a high-water mark at the time this 

 journal was founded. 



The first two decades of the century not only 

 witnessed the establishment of the fundamental 

 laws of chemical combination and their rational 

 explanation by means of the atomic theory ; they 

 also saw the enunciation of the gaseous laws ; the 

 discovery and application of voltaic electricity as 

 an analytic agent ; the isolation of the metals of 

 the alkalis and alkaline earths ; the determination 

 of the nature of the halogens ; and the discovery 

 of many new metallic elements. In 1802 these 

 were only twenty-three in number, as against 

 sixty-three at the present time. They saw, too, 

 the discovery of fulminating mercury and ful- 

 minating silver, acetylene, carbonic oxide, phos- 

 gene — some of which have played a large part 

 in the Great War, but which when first made 

 known were regarded as mere chemical curiosities, 

 incapable of application. This period also saw the 

 invention of the miner's safety lamp and the 

 creation of the gas-lighting industry — two., new 

 departures of which it is impossible to exaggerate 

 the consequences, immediate and remote. It 

 witnessed also the discovery of isomorphism, the 

 enunciation of the law of Dulong and Petit, and 

 the first synthesis, by Wohler, of an organic pro- 

 duct. 



The third decade brought us Faraday and the 

 discovery by him of tetrachlorethylene and per- 

 chlorethane ; the liquefaction of the gases ; the 

 isolation of benzene; the preparation of naphtha- 

 lene sulphonic acids ; and the formulation of the 

 laws of electro-chemical decomposition. It wit- 

 nessed also the activity of Graham ; the promulga- 

 tion of the law of gaseous diffusion ; the recogni- 

 tion of the basicity of acids and the constitution 

 of salts ; the establishment of the doctrine of com- 

 pound radicals by Liebig and Wohler; the dis- 

 covery by Dumas of chlorine substitution and the 

 publication of his theory of types. It saw also 

 the death of WoUaston and Davy, and the birth 

 of Cannizzaro, Berthelot, Kekul6, and Lothar 

 Meyer. The early 'thirties are memorable, too, 

 for the attempts made to regularise chemical 

 notation and for the gradual adoption of the 

 system of Berzelius. 



But, with the exception of the work of Graham 

 and Faraday, the decade 1830-40 is not particu- 

 larly remarkable for British contributions to 

 chemical science. Although the volume of pub- 

 lished work was no doubt considerable, it was 

 NO. 2610, VOL. 104] 



not of the epoch-making order. As Edward 

 Turner wrote, " the era of brilliant discovery in 

 chemistry appeared to have terminated for the 

 present." Thoughtful men deplored the condition 

 of British science at this period, and they were 

 concerned at the general apathy of the public with 

 respect to it. One result of their action was the 

 foundation, in 1831, of the British Association for 

 the Advancement of Science. At the same time, 

 it cannot be said that Continental workers were 

 much more active. Apart from those already 

 referred to, we find no noteworthy contribution 

 to the theory of chemistry. The extent of the 

 retrogression in this country may be judged from 

 the fact that at this time the number of com- 

 munications to the various societies, and to 

 scientific periodicals dealing with chemistry, was 

 not much more than half of what it was in 1802. 

 With the advent of the fourth decade there 

 was a great awakening. It was signalised by the 

 discovery of the first of the organo-metalloid 

 radicals by Bunsen in 1841 ; the recognition 

 of homology by Schiel in 1842; the early work 

 of Pasteur on racemic acid ; the synthesis of 

 acetic acid by Kolbe ; the dissociation of water by 

 heat by Grove ; the work of Frankland on ethyl 

 and zinc-ethyl ; the discovery by Wurtz of 

 the compound ammonias and their synthetical 

 formation by Hofmann ; and the elucidation of 

 the constitution of ether and the theory of 

 etherification by Williamson. This decade was 

 further made memorable by the creation, in 1841, 

 of the Chemical Society of London, and by the 

 foundation, in 1845, of the Royal College of 

 Chemistry. At that time organic chemistry was 

 scarcely studied in this country, and schools of 

 practical chemistry were very few in number here. 

 English chemists who sought instruction in opera- 

 tive chemistry and in the methods of original 

 investigation for the most part resorted to Liebig 

 at Giessen or to Wohler at Gottingen. Liebig 

 soon made his influence felt abroad, and his 

 memorable English tour in 1842 gave a strong 

 stimulus to the study of chemical science in this 

 country. One of its immediate effects was the 

 foundation of the Royal College of Chemistry, 

 with Hofmann, one of Liebig 's most brilliant 

 pupils, as its director. 



This was the first institution of its kind in 

 Great Britain in which chemistry was studied for 

 its own sake, and not merely as subordinate to 

 other professional training. Space does not per- 

 mit of any detailed account of its activities, or 

 of the circumstances which led to its absorption 

 into the School of Mines. It is only necessary 

 to recall the names of Warren de la Rue, Abel, 

 E. C. Nicholson, How, Bloxam, Blyth, Price, 

 Rowney, Muspratt, Mansfield, Field, Noad, 

 Brazier, Medlock, Crookes, Spiller, Tookey, 

 Church, Perkin, Groves, Valentin, Vacher, 

 O 'Sullivan, Duppa, McLeod, Reynolds, Griess, 

 Holzmann, Martius, Geyger — among the most 

 distinguished of Hofmann 's pupils and coadjutors 

 — to indicate the influence he exercised on the 

 development of chemistry in Great Britain during 



