532 



NA TURE 



[September 26, 1^95 



The precise mode of the formation of form-aldehyde in the 

 process of assimilation is a matter of dispute. But it is quite 

 clear that cither the carbon dioxide or the water, which are the 

 materials from which it is formed, must suffer dissociation. And 

 this requires a supply of enci^y to accomplish it. Warington 

 has drawn attention to the striking fact that in the case of the 

 nitrifying liactcrium, assimilation may go on without the inter\en- 

 tion of chlorophyll, the energy l>eing supplied by the oxidation 

 of ammonia. This brings us down lo the fact, which has long 

 been suspected, that protoplasm is at the Ixittom of the whole 

 business, and that chlorophyll only plays some subsidiary and 

 indirect part, perhaps, as Adolph Baeyer long agt) suggested, of 

 temjiorarily fixing carbon oxide like hivmoglobin, and so 

 facilitating the dissociation. 



Chlorophyll itself is still the subject of the careful study by Dr. 

 Schunck, originally commenced by him some years ago at Kew. 

 This will. I hope, give us eventually an accurate insight into the 

 chtniical constitution of this important substance. 



The steps in plant metabolism which follow the synthesis of 

 the proto-carlKihydrate are still obscure. Brown and Morris 

 have arrived at the unexpected conclusion that " cane-sugar is 

 the first sugar to Ijc synthesised by the assimilatory processes." 

 I made sonic remarks upon this at the time (Jciini. Chem. Soc, 

 1S93, 673), which I may be permitted to reproduce here. 



'• The point of view arrived at by Ixjtanists was briefly stated 

 bj- Sachs in the case of the sugar-lwet, starch in the leaf, 

 glucose in the petiole, cane-sugar in the root. The facts in the 

 sugar-cane seem to be strictly comparable {A'av BulUliii, 1S91, 

 35-41). Cane-sugar the botanist looks on, therefore, as a 

 ' reserve material.' We may call ' glucose ' the sugar ' currency ' 

 of the plant, cane-sugar its ' banking reserve.' 



" The immediate result of the diaslatic transfoimation of 

 starch is not glucose, but maltose. But .Mr. Horace Brown has 

 shown in his remarkable experiments on feeding barley embryos 

 that, while they can readily convert maltose into cane-sugar, they 

 altcgelher fail to do this with glucose. We may conclude, there- 

 fore, that glucose is, from the point of view of vegetable nutrition, 

 a somewhat inert lx)dy. On the other hand, evidence is 

 apfarcntly wanting that maltose plays the part in vegetable 

 metabolism that might be expected of it. Its conversion into 

 glucose may l>e perhaps accounted for by the constant presence 

 m plant tissues of vegetable acids. Bui, so far, the change 

 Would setm to be positively disadvanlagecus. I'erhaps glucose, 

 in the botanical sense, will prove to have a not very exact 

 chemical connotation. 



" That the connection between cane-sugarand starch is intimate 

 is a conclusion to which both the chemical and the botanical 

 evidence seims to point. And < n botanical grounds this would 

 seem to be equally Hue of its cf nnecliin with cellulose. 



" II must lie CI nfesstil that the conclusion that 'cane-sugar' 

 is the first sugar lo be s) nlhesised by the assimilatory processes 

 seems hard to rtconcilc with its prolable high chemical com- 

 plexity, and with the fact that, bctanically, it seems to stand at 

 the end and not at the beginning of the .series of metabolic 

 change," 



rRoroiTj\sMic Chemistry. 



The synthesis of proteids is the problem which is second only 

 in importance lo thai of caibohjdralcs. Lctw's views of this 

 deserve allenlive .siutly. Asparngin, as has long been suspected, 

 plays an imporlani [art. It has, he .'ays, two sources in the 

 plant. "It may either be foimid ilireclly fr< m glucose, 

 ammonia (or nitrates; and sulphates, or il maybe a Iransitoiy 

 product I]clwein protein-dccrmposilion and reconstruction from 

 the dagn-enls" (/cc. r;/. , 64). 



In the remarks I made lo ihc Chemical Society I ventured lo 



express my ci nviclii n ihal the chemical processes which look 



; ' ' ihe influercc of proloplnsm were prolrably cjf a 



'1 fri 111 ihi fe with which ihe chiniisi is ordinarily 



I ' ' • ' ■' ' ]iroduces a profu>ii n of mbslanres, 



riliiy, which Ihc cbiniist can only build 



w.iy. As Victor Meyer iP/ianii. Jotirii., 



I: "In order to isolalean 'irganic substance 



■ d lo ihe purely accidental properties of 



'ion.' In oilier words, ihe chemist 



i( molecular slabilily ; while il can- 



■■'il'laya pari in ihe processes of 



lespect. I am convinced lhal 



I of protoplasmic arliiily he 



s present limilalion.H, and be prei)are(l lo 



l»e more than one algebra, there may be 



will ll.ue I- 

 .idniil Ihnt 



xo. 1352, vol 



more than one chemisir)'. I am glad lo see thai a somewhai 

 similar idea has been suggested by other fields of inquiry. Prof. 

 Meldola (N.\rt'RE, xlii. 250) thinks lhal the mvestigalion 

 of photochemical processes "may lead to the recognition of a 

 new order of chemical .attraction, or of the old chemical attrac- 

 tion in a dilTerenl degree.' I am delighted lo see lhal the ideas 

 which were floaling, I confess, in a very nebulous form in my 

 brain are being clothed with greater precision by Loew. 



In the paper which I have alre-tdy quoted, he s-tys of proteids 

 {Im. til., 13) : "They are e.xieeilingjy iahi/f lompoiinds that can 

 be easily converted into relatively stable ones. A great hibiliiy 

 is the indispensable and necessary foundation for the production 

 of the various actions of the living protoplasm, for ihe mode of 

 motions that move the life-machinery. There is a sounc oj motion 

 in the labile position of atoms in molecules, a source thai has 

 hitherto not been taken into consideration either by chemists or 

 by physicists."" 



But I nmst say no more. The [iroblems lo which I might 

 invite attention on an occa-sion like this are endless. 1 have not 

 even attempted to do justice lo the work lhal has been accom- 

 plished amongst ourselves, full of interest and novelty as it is. 

 But I will venture to say this, lhal if capacity anti earnestness 

 afibrd an augury of success, the prosjiecls of the future of out 

 Section possess every element of promise. 



PHYSICS AT THE BRITISH ASSOCIATION. 



"TrHE proceedings of this Section were commenced by the 

 ■'■ delivery of Ihe presidential address by I'rof VV. M. Hicks. 

 In seconding the vote of thanks to Ihe I'resident. I'rof. Kitz- 

 gerald referred lo the possible change of mass with lemiiera- 

 lure, suggested in Ihe address, and pointed out that such a 

 phenomenon would show itself by a deviation of planetary 

 motions from strict conformity to Kepler's laws, owing to their 

 oh^nge of mass on cooling. 



I Sir Douglas t'.alton exhibited plans of the German Keichs- 

 anstalt, and of ihe new buildings in course of construction, anil 

 gave a more detailed account of Ihe man.igenienl of this insliuition 

 than is contained in his presidential address to the Association. 

 His object in reading the paper was to revive a movement set 

 on foot at a previous meeting by I'rof Oliver Lodge. The 

 Committee appointed at that lime lo consider ihe question of a 

 National Physical Laboratory for the United Kingdom m.tde bul 

 little progress, possibly because they did not prop<isc to de\elop 

 any existing institution. He suggested lhal Ihe scope of ihe 

 Kew Observatory should be extended so as to include research, 

 and that it be made the slarling-iioinl for the national 

 laboratory. 



A discussion followed, in which several members took part. 

 Prof Riicker lamented ihe wanl of concenlialion and organisa- 

 tion in research work, and thought a national laboralor)' might 

 remedy this. He regretted that ihe day was passing away when 

 a man could undertake Imlh leaching and research, because, in 

 his opinion, teachers should no! give up research. Prof Oliver 

 Lodge drew attention lo the enormous advanl.agcs possessed by 

 a national inslilulion, for carrying on researches extending over 

 a long period. In a universily laboratory such research would 

 possibly be discontinued wilh a change of professor. The 

 universilies woilld still do pioneer work, iliscovering new fields 

 of research and oblainiiig i»reliiiiinary results. Prof l-'it/gcrald, 

 on Ihc other hand, did not liiink il advisable lo hand over research 

 to a national laboralory, whereas he sirongly ailvocaled an 

 extension of ihe slandardising w<irk performed al Kew. He 

 believed lhal the highest kind of instruction was liaining in re- 

 .search work, and il was the function of the universilies lo give 

 this instruction. Instead of that, ihe professors are called upon 

 lo cram old knowledge inio immature and stupid students. The 

 Section h.is appointed a Commitlee lo reconsider the question 

 of a national laborat ory. / 



I'rof llenrici read a paper on the leaching of geometrical 

 drawing in schools, which wiis, he said, as a rule very bad. lie 

 pointed out lhal Euclid's constructions are generally followed, 

 Ihe use of the sel-s<piare being di.scarded and only straight eilges 

 and compasses used. He urged the desirability of (liscaoling 

 Eucliil in ihc teaching of geomelrical drawing, advocating ihe 

 U.SC of the set-s(juare from the very commencemeiil. Ihe 

 examples oughl lo lie so arranged thai a sludenl can verify his 

 constructions for himself; he lliercfore suggested the appuinl- 

 ineiit of a Committee lo report on the whole question and issue 



