502 



SCIENCE 



[N. S. Vol. XXXII. No. 824 



strained 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 to 

 revise some of the views which I have ad- 

 vanced here, should they ultimately be 

 found wanting. That, however, as I reas- 

 sure 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 any- 

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

 Notwithstanding this inadequate treat- 

 ment of the subject 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 or 

 the molten mass of a planet is an all-impor- 

 tant factor in the causation of vital phe- 

 nomena. 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 absorbed on the surface of a solution 

 system, is an indication that there are at 

 least some problems with a bearing on vital 

 phenomena yet to solve. Nevertheless, 

 what we have gained from our knowledge 

 of the laws of surface tension constitutes a 

 distinct step in advance, and a more ex- 

 tended application of the Gibbs-Thomson 

 principle may throw light on the causation 

 of other vital phenomena. To that end a 

 greatly developed science of microchem- 

 istry 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 con- 

 stituents, inorganic and organic, which 

 affect its physical state and thereby influ- 

 ence its activity. A. B. Macallum 



LITEEATUBE 



Barcroft and Brodie, Journ. of Physiol., vol. 

 32, p. 18; vol. 33, p. 52. 



Bernstein, Arch, filr die ges. Physiol., vol. 85, 

 p. 271. 



Bertliold, "Studien fiber Protoplasmameehanik," 

 Leipzig, 1886. 



Btitsehli, " Untersuchungen fiber Mikroskopische 

 Schaume," Leipzig, 1S92. 



Engelmann, Arch, fiir die ges. Physiol., vol. 2, 

 1869. 



Willard Gibbg, Trans. Conn. Acad, of Sciences, 

 1878; also, " Thermodynamische Studien," Leip- 

 zig, 1892, p. 321. 



Imbert, Arch, de Physiol., 5i6me ser., vol. 9, 

 p. 289. 



A. B. Macallum, Journ. of Physiol., vol. 32, p. 

 95, 1905. 



M. L. Menten, Trans. Canadian Inst., vol. 8, 

 1908; also. University of Toronto Studies, Physi- 

 ological Series No. 7. 



J. S. Macdonald, Proc. Roy. Soc, B., vol. 76, 

 p. 322, 1905; also. Quart. Journ. of Exp. Physiol., 

 vol. 2, No. 1, 1909. 



Quincke, Ann. der Physik und Ohemie, N.F., 

 vol. 35, p. 580, 1888. 



T. Brailsford Robertson, Bull. Physiol. Labora- 

 tory, University of California, 1909. 



J. Stoklasa, Zeit. fiir physiol. Chem., vol. 62, 

 p. 47. 



J. J. Thomson, " Application of Dynamics to 

 Physics and Chemistry," 1888. 



J. Traube, Arch, fiir die ges. Physiol., vols. 100 

 and 123. 



TEE EIGHTH INTERNATIONAL ZOOLOGICAL 

 CONGRESS IN GRAZ 

 Ts the week before the congress members 

 inspected the biological station in Lunz, with 

 its glass houses and ponds, the lower, middle 

 and upper lakes, the last 1,117 meters high, 

 and were shown the methods of research and 

 some of the results obtained. In Vienna, the 

 great Museum of Natural History, the zoolog- 

 ical laboratories of the university and the 

 vivarium were visited. The vivarium, under 

 the direction of Dr. Przibram, is a remarkable 

 institution for work in experimental biology 

 and evolution. There are series of rooms in 

 which the temperature, light and other condi- 

 tions of existence may be under control, and 



