THE BEGINNINGS OF LIFE. 119 



librium to another mode of statical equilibrium, if it 

 take place with sufficient rapidity and be associated 

 with a concurrent process of growth, will give rise to 

 that continuous series of molecular changes which cha- 

 racterize what we know as ^ living "* matter. And yet 

 the molecular aggregate which displays this continuous 

 responsive mobility and power of self-division — because 

 it has been called a ^living' thing, and because theo- 

 retical notions have been formed concerning '^life' — has 

 been supposed to be separated from other closely-related 

 kinds of matter by an impassable gulf. 



Irresistibly the thought arises which may prompt us 

 to ask. What higher modes of aggregation exist on the 

 surface of other planets belonging to our own or 

 different solar systems ? Is it necessary to suppose that 

 the highest modes of molecular aggregation which have 

 appeared upon our earth, are at all similar to those 

 which have arisen under the continued influence of 

 more or less dissimilar conditions? May we not rather 

 suppose, that other highest modes of aggregation may 

 exist totally different from our own, each of which, to 

 whatsoever planet or system it belongs, may possess 

 qualities so subtle as to make it comparable only with 

 that which we call ^ living " matter ? 



jusqu'a produire une division complete de certains globules en deux, 

 de la meme maniere qu'on voit s'opdrer la scission par etranglement 

 graduel de certaines cellules vegetales et animales.' (Robin, ' Traite du 

 Microscope,' 1871, p. 562.) 



