The Energy of Segmentation 299 



they claim as to a finer structure and more detailed events is to be 

 admitted, but that does not invalidate the hypothesis w^hich I have 

 advanced, that all these structures and forces result in two opposed 

 forces, or can be looked upon as if they were two such resultant 

 forces. 



This is in accordance with the view taken of the purpose of an 

 hypothesis, for example, by Boltzmann;* it is not that of seeing 

 through (durchschauen) the mechanism of nature, but rather of 

 giving a simple presupposition by which it becomes possible to 

 "reckon" (berechnen) the phenomena of nature with the greatest 

 closeness. 



Regarding our procedure, then, as one justified both by pre- 

 cedent and by the results to which it leads, our hypothesis may 

 be stated in a more complete and detailed manner as follows: 

 It is, that normal fertilization brings about — perhaps somewhat 

 gradually, and up to possibly the time of the metaphase — an 

 increase in the resultant internal pressure directed against the cell 

 membrane; that, as a result of this pressure-increment, there is 

 established normally an uncompensated potential difference be- 

 tween the pressure which is directed externally from within and 

 the opposed internally directed pressure of the membrane; that as 

 the result of, or identical with the necessary transfer of energy 

 under such conditions, segmentation takes place, with its accom- 

 panying increase of surface; that, however, by supplementing the 

 pressure of the membrane, /. e., by compensating this internal 

 pressure-increment just before each segmentation, this event can 

 be inhibited, and thereby the numerical value of the internal pres- 

 sure, and its decrease with each segmentation determined. In 

 this way, for each segmentation, equilibrium will be produced and, 

 thereby, reversibility, so that with these data, together with the 

 surfaces and especially the volumes of the various division-stages 

 determined by measurement, a sufficient basis for the application 

 of the appropriate empirical law, and the computation of the 

 energy of segmentation in accordance with equation [8], will be 



'Ueber die Methoden der theoretischen Physik, in Dyck.Katalog math. Modelle. Munich, 1892' 

 Cited by Helm, Die Energetik. Leipzig, p. 338, 1898. 



