112 THE GERM THEORY OF DISEASE. 



All forms of life are continually taking into themselves 

 fresh increment of matter in some form. This fresh incre- 

 ment of matter is converted into other forms, for the support 

 of the energies of that life which performed this conversion; 

 and when this is accomplished, it must give way to fresh in- 

 crements of matter, which undergo similar remoleculizations. 

 The old must give place to the new. There is no such thing 

 as standing still, except with certain definite provisions for 

 temporary inactivity. Otherwise than this, inactivity is 

 death. As new material is added, the old must be disposed 

 of, must be cast out, or built up into formed material, where 

 it takes no further part in the physiological activities of the 

 organism. Continuous molecular change of matter is the 

 law of physiological existence. In other words, the remolecu- 

 lization of matter is necessary to the support of life ; and 

 when this remoleculization ceases to be performed by the life 

 force, except under the provisions of rest, that life ceases to 

 exist. 



As the living form must be supported by fresh increment, 

 so it must give back excrement. Life is not to be supported 

 by the continuous remoleculization of the same matter. After 

 it has once accomplished its function in the economy, it be- 

 comes unfitted for further physiological use, and is disposed 

 of in one of two ways. It is either built into fixed material, 

 or it is cast out as excrement. In either case it is disassociated 

 with the physiological activity of the organism. The sum of 

 the excrement, fixed and formed material, must, in all cases, 

 equal the sum of the increment. There is nothing lost, nothing 

 gained. All increment not present in the organism, must 

 have been given back to the outside world as excrement, no 

 matter what the form of life. 



There is a general law to be observed in the formation of 

 excrementitious matters. Liebig, while opposing the life- 



