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SCIENCE 



[N. S. Vol. XXXII. No. 823 



and colloidal ' ' solutions. ' ' The importance 

 of this knowledge consists in the fact that 

 protoplasm, "the physical basis" of life, 

 consists mainly of colloids and water. Till 

 eleven years ago what was known regard- 

 ing colloids was derived chiefly from the 

 researches of Graham (1851-62), Ljubavin 

 (1889), Barus and Schneider (1891), and 

 Linder and Picton (1892-97), who were 

 the pioneers in this line. In 1899 were 

 published the observations of Hardy, 

 through whose investigations very great 

 progress in our knowledge of colloids was 

 made. In 1903 came the invention of the 

 ultramieroscope by Siedentopf and Zsig- 

 mondy, by which the suspension character 

 of colloid material in its so-called "solu- 

 tions" was visually demonstrated. During 

 the last seven years a host of workers have 

 by their investigations greatly extended 

 our knowledge of the physical and chemical 

 properties of colloids, and now the science 

 of collochemistry bids fair, the more it de- 

 velops, to play a very important part in all 

 studies bearing on the constitution and 

 properties of living matter. 



Then, also, there are the phenomena of 

 surface tension. This force, the natvire of 

 which was first indicated by Segner in 

 1751, and described with more detail' by 

 Young in 1804 and La Place in 1806 in the 

 expositions of their theories of capillarity, 

 was first in 1869 only casually suggested 

 as a factor in vital processes by Engel- 

 mann. Since the latter date and until 

 1892, when Biitschli published his obser- 

 vations on protoplasmic movements, no 

 serious effort was made to utilize the prin- 

 ciple of this force in the explanation of 

 vital phenomena. Even to-day, when we 

 know more of the laws of surface tension, 

 it is onlj^ introduced as an incidental factor 

 in speculations regarding the origin of 

 protoplasmic movement and muscular con- 

 traction, and yet it is, as I shall maintain 



later on in this address, the most powerful, 

 the most important of all the forces con- 

 cerned in the life of animal and vegetable 

 cells. 



It may be gathered from all that I have 

 advanced here that the chief defect in bio- 

 logical research has been, and is, the fail- 

 ure to apply thoroughly the laws of the 

 physical world in the explanation of vital 

 phenomena. Because of this too much 

 emphasis is placed on the division that is 

 made between the biological and the phys- 

 ical sciences. This division is very largely 

 an artificial one, and it will in all probabil- 

 ity be maintained eventually only as a 

 convenience in the classification of the sci- 

 ences. The biologist and physiologist have 

 to deal with problems in which a wide 

 range of knowledge is necessary for their 

 adequate treatment; and, if the individual 

 investigator has not a very extensive train- 

 ing in the physical sciences, it is impossible 

 for him to have at his command all the 

 facts bearing on the subject of his research, 

 unless the problem involved be a very nar- 

 row one. The lack of this wide knowledge 

 of the physical sciences tends to specialism, 

 and, as the specialism is ever growing, it 

 will produce a serious situation eventually, 

 for it will develop a condition in the sci- 

 entific world in which coordination of effort 

 and a broad outlook will be much more 

 difficult than is the case now. 



This growing defect in the biological 

 sciences can only be lessened by the in- 

 sistence of those in charge of advanced 

 courses in biological and physiological lab- 

 oratories that only they whose training is 

 of a very wide character should be allowed 

 to take up research. It is, perhaps, futile 

 to expect that such a rule will ever be en- 

 forced, for in the keen competition between 

 universities for young teachers who have 

 made some reputation for original investi- 

 gation there may not be too close a scrutiny 



