138 Organic Physics. [ February, 
during sleep. It is oxidation of the combustible materials of the 
sap current, and yields energy to assist in chemical synthesis, 
Thus plants display only one of the life processes. Their whole 
life is passed in the sleeping, assimilative state. They fail to 
attain the waking, active state. i 
This distinction is, indeed, not an absolute one. To a limited 
extent oxidation of the protoplasmic tissues takes place in plants, 
and to that extent motive energy is possible. In those organs of 
plants which are specially rich in protoplasm, the leaves and 
flowers, motor activity is frequently displayed; and in the meat 
eating plants, in which chemical synthesis is less exhaustive of 
energy, there occur at times rapid and well-defined motions, with 
marked indications of nervous and muscular functions. As@ 
animals. They are periodical, but the periods rapidly succ 
each other, so that there is little or no visible indication ofa 
may contain, it certainly contains highly complex, albumi 
mplecules, which are its active principles. And the activity ° 
these molecules appears to be strictly chemical in character, 
to consist of the following double process. They have an affinity 
for oxygen. which removes some of their elements, reduces t 
complexity of composition, and yields free energy. In this t 
duced state their affinity for oxygen weakens, they acquire # 
affinity for nutrient molecules, combine with the latter, lock 4 
energy in doing so, and regain their molecular complexity. 4 
life consists in the periodical succession of these two process 
In all the higher phases of life there are mechanical appliant 
for the utilization of the energy set free in the first of these ] 
cesses; but the basis of all life, its fandamental condition, 13 
chemical activity of albuminoid molecules. To comprehend. 
then, we must first comprehend protoplasm; and some fuller 
sideration of the characteristics above given is desirable. 
