NATURE OF LIFE. 5 



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 or- 

 ganisation is not an intrinsic and indispensable condition of 

 vital phenomena. 



Such an intrinsic arid indispensable condition is, however, 

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

 which has been applied the name of " protoplasm " (the " bio- 

 plasrii " of Dr Beale). Without some such a material substra- 

 tum, or medium upon which to work, no one vital phenome- 

 non 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 inseparably connected with protoplasm. In otheT 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 mat- 

 ter 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 appKed 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 

 40° — 50° 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 

 nucleated, is the formal basis of all life,* there, nevertheless, 



* It has not yet been shown that the living matter which we designate 

 jy the convenient term of ' ' protoplasm " has universally and in all cases 

 a constant and undeviating chemical composition ; and there is, indeed, 

 reason to believe that this is not the case. It is .also certain that there are 

 other materials, the exact use of which we do not at present know, which 



