vii. J ON THE PHYSICAL BASIS OF LIFE. 113 



of chemical analysis to the living bodies which have yielded 

 them. 



One fact, at any rate, is out of reach of such refinements, and 

 this is, that all the forms of protoplasm which have yet been 

 examined contain the four elements, carbon, hydrogen, oxygen, 

 and nitrogen, in very complex union, and that they behave 

 similarly towards several reagents. To this complex combina 

 tion, the nature of which has never been determined with 

 exactness, the name of Protein has been applied. And if we 

 use this term with such caution as may properly arise out of our 

 comparative ignorance of the things for which it stands, it may 

 be truly said, that all protoplasm is proteinaceous, or, as the white, 

 or albumen, of an egg is one of the commonest examples of a 

 nearly pure proteine matter, we may say that all living matter 

 is more or less albuminoid. 



Perhaps it would not yet be safe to say that all forms of pro 

 toplasm are affected by the direct action of electric shocks ; and 

 yet the number of cases in which the contraction of protoplasm 

 is shown to be effected by this agency increases every day. 



Nor can it be affirmed with perfect confidence, that all forms 

 of protoplasm are liable to undergo that peculiar coagulation at 

 a temperature of 40 50 centigrade, which has been called 

 &quot; heat-stiffening,&quot; though Klihne s beautiful researches have 

 proved this occurrence to take place in so many and such 

 diverse living beings, that it is hardly rash to expect that the 

 law holds good for all. 



Enough has, perhaps, been said to prove the existence of a 

 general uniformity in the character of the protoplasm, or 

 physical basis, of life, in whatever group of living beings it 

 may be studied. But it will be understood that this general 

 uniformity by no means excludes any amount of special modifi 

 cations of the fundamental substance. The mineral, carbonate 

 of lime, assumes an immense diversity of characters, though no 

 one doubts that, under all these Protean changes, it is one and 

 the same thing. 



I 



