NATURE OF LIFE. 5 



are capable of manifesting all the essential phenomena of life ; 

 they are produced from bodies . like themselves ; they eat, 

 digest, and move, and exhibit distinct sensibility to many ex- 

 ternal impressions. Furthermore, many of these little masses 

 of structureless jelly possess the power of manufacturing for 

 themselves, of lime, or of the still more intractable flint, 

 external shells of surpassing beauty and mathematical regu- 

 larity. In the face of these facts we are therefore compelled 

 to come to the conclusion that life is truly the cause and not 

 the consequence of organisation ; or, in other words, that 

 organisation is not an intrinsic and indispensable condition of 

 vital phenomena. 



Such an intrinsic and indispensable condition is, however, 

 to be found in the 1 presence of a " physical basis," to which 

 has been applied the name of "protoplasm" (the "bioplasm" 

 of Dr Beale). Without some such a material substratum or 

 medium upon which to work, no one vital phenomenon can 

 be exhibited. The necessary forces may be there, but in the 

 absence of this necessary vehicle there can be no outward and 

 visible manifestation of their existence. Life, therefore, as we 

 know it, and as far as we know it, may be said to be insepar- 

 ably connected with protoplasm.- In other words, protoplasm 

 bears to life the same relation that a conductor does to the 

 electric current. It is the sole medium through which life can 

 be brought into relation with the external world. There is, 

 however, as yet, no reason to believe that protoplasmic matter 

 holds any other or higher relation to life, or that vital 

 phenomena are in any way an inherent property of the matter 

 by which alone they are capable of being manifested. 



As regards its nature, protoplasm, though capable of form- 

 ing the most complex structures, does not necessarily exhibit 

 anything which can be looked upon as organisation, or dif- 

 ferentiation into distinct parts ; and its chemical composition 

 is the only constant which can be approximately stated. It 

 consists, namely, in all its forms, of the four elements, carbon, 

 hydrogen, oxygen, and nitrogen, united into a proximate 

 compound to which Mulder applied the name of " proteine," 

 and which is very nearly identical with albumen or white-of- 

 egg. It further appears probable that all forms of protoplasm 

 can be made to contract by means of electricity, and " are 

 liable to undergo that peculiar coagulation at a temperature of 

 4o-5o centigrade which has been called 'heat-stiffening'" 

 (Huxley). 



If we admit, then, with Huxley and the admission re- 

 quires some qualifications that "protoplasm, simple or 



