TlUNS.VCTIOiNS OK SECTION IJ. 



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nltcntioii 19 tlml of tlK'niin-fliciiiistrv, a siilijfrt upmi 'wliich in tlio future llit) 

 i'liiuiiliition ol' (Ivniimiciil <'lirnii.-<lry must, rest, luid (ino wliirh iilrciiily |»V()cliu!ii>' 

 the tiMitli of tlio pivat. pviuciplo of tlio con.sorviitiuii nf ciiovpy in all cmscs df 

 fliciiiical lis well as of iiliyslcul ('luiii^n'. I'.iit lirrc, iiltlmnj^li tin- inalcrial.s iiitlinln 

 coUt'clcil iiio of vt'iy Cdii.-i'h raliii) auiouut and valur, tlu- time lins nol yi't airiwd 

 for i'xi)n'>-iii,Lr tlicsi. results in ;;encral terms, and we must, tlierefire, lie coii- 

 ti'iit tu unie jiro^ress in special line" !;nd wait fur the evjiansiDn into wider areas. 

 Jleferenee may, however, bn pr.>])urly maile to one interi'stin^r observation of 

 (Tciu'ral sifjiiificance. It is well known Unit, wiiile, in niost instances, tlio act 

 iif ciiuiliination is accompanied liy evolution of heat— tliat is, wjiiist the potential 

 cncrij'v of most comliiniii^j; hodii's is greater tliiin that of most compounds — cii.ses 

 iiccar in which the reversl^ of this is true, and heat in alisorhed in comliiiiatioii. 

 Ill su(!h cases tho compound readily underf,'-oe3 decomposition, frequently sudth'idy 

 1111(1 with ex])losion. Acetylenes and cyanoi^'en .-eem to lie exceptions ro this 

 rule, inasmuch as, whilst their component elements reijuire to have ener;.'y atlded 

 to them in order to enable them to combine', the compoinids ap]iear to be very 

 stable bodies. JJurtliidot lias explaiiu'd this cniunia by showin;; that, just as wo 

 may if;nito a mass of dynamite wiliiout danr;er, whilst .'xplosiou takes jilaco if we 

 airitati; the molecules by a detonatoi', so acetyb'ne and cyaiio;j-en hum, as we 

 know, quietly when i;rnited,but wiieii thi'ir molecules are shaken by the detonalioii 

 of even a minute quantity ol' fuhninate, the conslitiieiits fly apart with explo>ive 

 violence, carbon and hydrojreii, or carbon and iiilro^'eii heiiii^' set free, and the- 

 quantity of heat absorbed in the act of combination beinu' suddenly liberated. 



In conclusion, wbilst far from ])roposin<f even to mention all t!ie important 

 s.ti'iis by which onr science has ailvancod since the year 184S, I cannot refrain 

 from referring to two more. In the first ])lace, to that discovery, more tin 'i fore- 

 slmdowed by Faraday, of tbo liqu(d'action of the so-called permanent pisos by 

 I'ictet and Cailletet ; and secondly to that ^f the laws of dissociation as investi- 

 mted by Deville. The former, iiicludini,' Andrews's discovery of tbe crit ical ]ioint. 

 indicates a connection, long unseen, between the li"uid and the gaseous states of 

 matter; the latter has opened out entirely fresh fields for research, and has given us 

 new views concerning tho stability of chemical compounds of great importance 

 and interest. 



Turning for a moment to nnotlier topic, we feel that, although science knows 

 no nationalities, it is impossibh^ for those who, like ourselves, exhibit strong' 

 national traits to avoid asking whether we Anglo-Saxons hold our own, as 

 compared with other nations, in the part we have jilayed and are i)laying in 

 the development of our science, ^\'ith regard t(3 the past, the names of -IJoyle, 

 Cavendish, Priestley, Dalton, Black, Uavy, are suflicient guarantees that the 

 English have, to say the least, occupied a jiosition second to none in the early 

 annals of chemistry. How has it Tieen in the era which I have attempted to 

 describe':' What is the present position of English elieniistry, and what its lordi- 

 out for the future ? In endeavouring to make this estimate 1 would take the 

 widest ground, including not only the efforts made to extend the boundaries of our 

 science by new discovery, both in tho theoretical and applied branches, but 

 also those which have the no less important aims of spreading the knowledge of 

 the subject amongst the people, and of establishing industries dependent on cbemi- 

 cal principles by which the human race is benefited. Taking this Avide .lew, 1 

 think wo may, without hesitation, allirm that the progress which chemistry has 

 made through the energies of the Anglo-lSaxon race is not less than that made by 

 any other nation. 



In so fav as pure science is concerned I have already given evidence of the not, 

 inconsiderable part which English chemists have played in the progress since 1848. 

 We mu.sc, however, acknowledge that the number of original chemical papers now 

 publislied in our language is much smaller than that appearing in the German 

 tongue, and that the activity and devotion displayed in this direction by the heads 

 of German laboratories may well be laid to heart by some of us in Ivnglaud ; yet, 

 on the other hand, it must be remembered that the circumstances of difierent coun- 





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