NUTRITION. 267 



It is interesting, however, to inquire by what means the 

 soluble pabulum is caused to pass into the bioplasm. No 

 form of attraction or affinity that we are acquainted with 

 will account for the passage of pabulum towards and into 

 the living matter. The question is one upon which I have 

 ventured to speculate. The tendency which every mass of 

 bioplasm exhibits to divide into smaller portions, each part 

 appearing to move away from other portions, suggests the 

 idea of there being some power of centrifugal movement in 

 operation. The moving away of particles from a centre 

 would necessarily create a tendency of the fluid around to 

 move towards the centre \ I think, therefore, that the 

 nutrient pabulum is, as it were, drawn in by centripetal, 

 currents, excited by the centrifugal movements of the par- 

 ticles of the living bioplasm. How it is that vitality gives 

 to matter the power of moving away from centres I cannot 

 even attempt to explain. That this is so, is rendered pro- 

 bable by many general facts, open to the observation of all, 

 as well as by the observation of some wonderful phenomena 

 which can be made with the aid of the highest powers 

 of our microscopes. 



But the point in which every nutritive act differs 

 essentially from every other known change is this : the com- 

 position and properties of the nutrient matter are com- 

 pletely altered, its elements being entirely rearranged, so 

 that compounds which may be detected in the nutrient 

 matter are no longer present when this has been taken up 

 by the matter to be nourished. The only matter capable 

 of effecting such changes as these is living matter, and it is 

 very remarkable that when this matter ceases to live, we 

 do not detect amongst the compounds formed at its death 



