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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 re-agents. To this 

 complex combination, 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 j or, as 

 the white, or albumen, of an egg is one of the common- 

 est 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 

 protoplasm are affected by the direct action of electric 

 shocks ; and yet the number of cases in which the con- 

 traction of protoplasm is shown to be affected 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 the temperature 

 of 40 degrees 50 degrees centigrade, which has been 

 called "heat-stiffening," though Kiihne's beautiful re- 

 searches 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 physi- 

 cal basis of life, in whatever group of living beings il 

 may be studied. But it will be understood that this gen- 

 eral uniformity by no means excludes any amount of 



