Protoplasmic Currents and Vital Force. 



■v 



By Pjrof. A. L. Herrera. 



I have lately stated that some currents of granules may lead to the 

 formation of a pseudopodium in my synthetic protoplasm observed 

 under the microscope. 1 What occurs is an exact imitation of the 

 natural phenomenon. The internal energy of the said currents 

 expends itself in external movements. The fluid loaded with granula- 

 tions strikes, as it were, a blow as it dashes against the endosarc, 

 or the limiting membrane of the protoplasm, and pushes it outwards. 



But these currents play a more important part ; they induce, 

 indeed, the following processes : — 



1st. Benovation of the surfaces of contact between the oxidisable 

 parts and the external oxygen. More effective elimination of carbon 

 dioxide. 2 



2nd. Conveyance of the nutritive particles and residues. Nutrition 

 of the masses of alveolar protoplasm, which fulfil the functions of 

 glands, etc., according to principles of Van't Hoff, Becquerel, 3 and 

 Loeb. Circulation of the reserves and circulation in the zymoses. 



3rd. Deposition of certain materials and separation of some others 

 according to their solubility, density, and so forth. Concentric forma- 

 tions, incrustations, etc. 



The study of these internal currents is, one may say, the chief 

 aim of physiology. They may be explained in terms of known 

 physico-chemical causes rather than by an undiscovered and undis- 

 coverable vital force. The causes are — 



A. Diffusion and osmotic currents. 



B. Heat. Oxidations. 



C. Ingestion of the materials that support the phenomena of 



diffusion and oxidation. 



D. Partial vacua and changes of every kind in internal pressure, 



induced by evaporation, etc. 



1 Natural Science, August 1898; Bull. Soc. Zool. France, 1898, p. 119; American 

 Naturalist, December 1898. 



2 See A. L. Herrera and D. Vergara Lope, " New Theory of Respiration." Congress at 

 Moscow, 1898. 



3 Becquerel, "Les forces electro-capillaires dans les phenomenes de nutrition" Comptcs 

 rendus Acad. Sci. Paris, 15 fevrier 1875. 



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