80 WHAT IS LIFE ? 



Let us consider this, for the sake of making our ideas 

 clear, the centre atom in our diagrams (fig. 5 A to D), 

 then we have the initial fundamental idea of Life. 



We will now consider the evidence of the specialist. 

 Professor E. A. Schafer states, 1 u All are aware that 

 the body of every animal and of every plant is made 

 up of minute corpuscles 2 which are formed of proto- 

 plasm, and which contain in every case at least one 

 nucleus. The protoplasm and the nucleus form the 

 living substance of the cell. Other substances may 

 be present, but they are, in a sense, outside the nucleus 

 and protoplasm, not incorporated with their substance. 

 Apart from a few details relating to the structure of 

 the nucleus, this was, until quite lately, practically all 

 that we knew regarding the parts composing either 

 the animal or the vegetable cell. There appears, how- 

 ever, to be yet another something which, although in 

 point of size it is of very insignificant dimensions, yet 

 in point of function may perhaps be looked upon as 

 transcending in importance, in some respects, both the 

 protoplasm and the nucleus. Not many years ago it 

 was noticed by various observers that in certain 

 specialised animal cells the protoplasm showed a ten- 

 dency to radiate from or converge towards a particular 

 point, and on further investigation it was found that at 

 this point there was a minute particle. This observa- 

 tion, which began, as we have seen, upon specialised 

 cells, was, after a little while, found to hold good for 

 other and yet other cells, until, at the present time, 

 we believe that in every celt of the animal or plant body 



1 The President's Address, British Association Meeting, Oxford, 

 1894. Section I. Physiology, by Professor E. A. Schafer, F.R.S. 



2 i.e. Cells. 



