452 



NATURE 



[October 6, 1910 



The position which I occupy imposes limits, and there 

 enters also the personal factor to account in part for the 

 failure to achieve the result at which I aimed. But there 

 is, besides, the idea that in applying the laws of surface 

 tension in the explanation of vital phenomena 1 am pro- 

 ceeding along a path into the unknown which has been 

 as yet only in a most general way marked out by pioneer 

 investigators, and in consequence, to avoid mistakes, I 

 have been constrained to exercise caution, and to repress 

 the desire to make larger ventures from the imperfectly 

 beaten main road. Perhaps, after all, I may have fallen 

 into error, and I must therefore be prepared to recall or 

 lo revise some of the views which I have advanced here 

 should they ultimately be found wanting. That, however, 

 as I reassure myself, is the true attitude to take. It is a 

 far cry to certainty. As Duclaux has aptly put it, the 

 reason why Science advances is that it is never sure of 

 anything. Thus I justify my effort of to-day. 



Notwithstanding this inadequate treatment of the sub- 

 ject of surface tension in relation to cellular processes, I 

 hope I have made it in some measure clear that the same 

 force which shapes the raindrop is an all-important 

 factor in the causation of vital phenomena. Some of 

 the latter _may not thereby be explained. We do not 

 as yet know all that is concerned in the physical 

 state of solutions. The fact, ascertained by Rona and 

 Michaelis, that certain sugars, which neither lower nor 

 appreciably raise surface tension in their solutions, 

 condense or are adsorbed on the surface of a solu- 

 tion system, is an indication that there are at least some 

 problems with a bearing on vital phenomena yet lo solve. 

 Nevertheless, what we have gained from our knowledge 

 of the laws of surface tension constitutes a distinct step 

 in advance, and a more extended application of the Gibbs- 

 Thomson principle may throw light on the causation of 

 other vital phenomena. To that end a greatly developed 

 science of microchemistry is necessary. This should supply 

 the stimulus to enthusiasm in the search for reactions that 

 will enable us to locate with great precision in the living 

 cell the constituents, inorganic and organic, which affect 

 its physical state and thereby influence its activity. 



hitcralure. 



Barcroft and Brodie, Joiirn. of Physiol, vol. xxxii., p. 

 i8 ; vol. xxxiii., p. 52. 



Bernstein, Aich. fiir die gcs. Physiol, vol. Ixxxv., 

 p. 271. 



Berthold, " Studien iiber Protoplasmamechanik," Leip- 

 zig, 1886. 



Butschli, " Untersuchungen iiber Mikroskopische 

 Schaume," Leipzig, 1892. 



Engelmann, Arch, fur die gcs. Physiol, vol. ii., 1869. 



Willard Gibbs, Trans. Conn. Acad, of Sciences, 1878; 

 also " Thermodynamische Studien," Leipzig, 1892, p. 321. 



Imbert, Arcli. de Physiol, ^\ime ser., vol. ix., p. 289. 



A. B. Macallum, Journ. of Physiol, vol. xxxii., p. 95, 

 1905- 



M. L. Menten, Trans. Canadian Inst., vol. viii., 1908; 

 also " University of Toronto Studies," Phvsiological Series 

 No. 7. 



J. S. Macdonald, Proc. Roy. See, B, vol. Ixxvi., 

 p. 322, 190S; also Quart. Journ.' of E.\p. Physiol, vol. ii.. 

 No. I, 1909. 



Quincke, Ann. der Physik und Chcmie, N.F. vol. xxxv., 

 p. 580, 188S. 



T. Brailsford Robertson, Bull. Physiol. Laboratorv, 

 University of California, 1909. 



J. Stoklasa, Zeit. fiir physiol Chem., vol. Ixii., p. 47. 



J. J. Thomson, " Application of Dvnamics to Physics 

 and Chemistry," 1888. 



J. Traube, Arch, fiir die ges. Physiol, vols. c. and 

 cxxiii. 



SECTION K. 



BOTANY. 



Opening Address by Prof. James \V. H. Trail, M.A., 



M.D., F.R.S., President of the Section. 

 The honour conferred in the election to be President 

 for the year of the Botanical Section of the British Associa- 

 tion imposes the duty of preparing an address. I trust 

 that my selection of a subject will not be attributed by 



NO. 2136, VOL. 84] 



anyone to a want of appreciation of the worth and import- 

 ance of certain sides of botanical research to which I 

 shall have less occasion to refer. These have been 

 eloquently supported by former Presidents, and I take 

 this opportunity to express the thanks I owe for the 

 benefit received from their contributions to the advance- 

 ment of the science of botany. They have told us of the 

 advance in departments of which they could speak as 

 leaders in research, and I do not venture to follow in their 

 steps. My subject is from a field in which I have often 

 experienced the hindrances of which I shall have to speak, 

 both in personal work and still more as a teacher of 

 students, familiar with the many difficulties that impede 

 the path of those who would gladly give of their best, but 

 find the difficulties for a time almost insurmountable, and 

 who are too frequently unable to spare the time or labour 

 to allow of their undertaking scientific investigations that 

 they might well accomplish, and in which they would 

 find keen pleasure under other conditions. Those whose 

 tastes lie in the direction of studying plants in the field 

 rather than in the laboratory are apt to find themselves 

 hampered seriously if they seek to become acquainted with 

 the plants of their own Mcinity ; and, if they wish to 

 undertake investigations in the hope of doing what they 

 can to advance botanical science, they may find it scarcely 

 possible to ascertain what has been already done and 

 recorded by others. 



For a time the knowledge of plants was too much con- 

 fined to the ability to name them according to the system 

 in vogue and to a knowledge of their uses, real or 

 imagined. The undue importance attached to this side of 

 the study, even by so great a leader as Linna?us, naturally 

 led to a reaction as the value of other aspects of botany 

 came to be realised, and as improvements in the instru- 

 ments and methods of research opened up new fields of 

 study. The science has gained much by the reaction ; but 

 there is danger of swinging to the other extreme and of 

 failing to recognise the need to become well acquainted 

 with plants in their natural surroundings. The oppor- 

 tunities for study in the laboratory are so great and so 

 much more under control, and the materials are so 

 abundant and of so much interest, that there is for many 

 botanists a temptation to limit themselves to such work, 

 or at least to regard work in the field as subordinate to 

 it and of little value. It is scarcely necessary to point out 

 that each side is insufficient alone. Yet some find more 

 pleasure in the one side, and do well to make it their chief 

 study ; while they should recognise the value of the other 

 also, and learn from it. 



It is especially on behalf of the work in the field that 

 I now wish to plead. There are few paths more likely 

 to prove attractive to most students. The study of the 

 plants in their natural environments will lead to an 

 understanding of their nature as living beings, of their 

 relations to one another and to other environments, of the 

 stimuli to which they respond, and of the struggle for 

 existence that results in the survival of certain forms and 

 the disappearance of others. In this way also will be 

 gained a conception of the true meaning and place of 

 classification as an indispensable instrument for accurate 

 determination and record, and not as an end in itself. To 

 one that has once gained a true insight into the pleasure 

 and worth of such studies, collections made for the sake 

 of mere possession or lists of species discovered in a locality 

 will not suffice. Many questions will arise which will 

 prove a constant source of new interest. From such studies 

 a deep and growing love for botany has in not a few cases 

 arisen. 



The British flora has interested me for upwards of forty 

 years, and has occupied much of my attention during that 

 time — not only as desirous to aid by my own efforts to 

 extend our knowledge of it, but also, as a teacher, seek- 

 ing to assist my students to become able to do their parts 

 also, and making use of the materials within reach to 

 enable me to help them. Thus our present knowledge of 

 the plants of our own country has become known 

 to me, and the difficulties of acquiring that knowledge 

 have also . become known through both my own experi- 

 ence and those of my students. The nature of the 

 hindrances and difficulties that at present bar the way 

 has also become familiar, as well as the steps to be taken 



