266 Organic Physics. [ March, 
koffer and Voit that the expired carbonic acid is no measure of 
the oxygen simultaneously inspired. During the day the expired 
carbonic acid is considerably in excess of that due to the oxygen 
. inspired. During the night the opposite is the case, more oxygen 
is breathed in than is expired. Thus a portion of the oxygen re- 
ceived during sleep seems to be retained in the body, for use 
during the waking period. It probably partly lies in the blood 
corpuscles, but it must also be largely laid up in the muscles, from 
their power of contraction long after removal from the body, 
Perhaps it is stored in all the protoplasmic tissues. 
These facts lead to definite views concerning organic action 
Nutrition and oxidation constantly go on, yet each has its two dis- 
tinct phases. The primary phase of oxidation is accompanied by 
a secondary phase of nutrition. Protoplasm is oxidized and re- 
duced. Part of the energy yielded is employed in the capture, 
` mastication and digestion of food, its absorption and carriage by 
the blood, and its storage in the tissues, or in the cells. 
During the resting or nutritive period these operations cease 
Primary nutrition comes into play, and is aided by secondary oxF 
dation. The products of primary oxidation are again attacked by | 
oxygen, and some of their molecules still further reduced. But 
this chemical action yields an energy which aids others of their 
molecules to combine with the stored nutrient molecules, to the 
reproduction of protoplasm. This is the primary nutritive p% 
cess. It isa process of double decomposition which is in lo 
accordance with many inorganic chemical actions. There 8* 
splitting asunder of one substance, whose sundered molecules 
combine with two other attracting substances, to the formation 
two new compounds. In this process only a portion of the yei 
- gen received during sleep is employed. The remainder is or 
up in the protoplasmic tissues, for use during the waking P&™ 
The true process of organic action may possibly be something 
like the following: The activity of protoplasm arises from w 
affinity of oxygen for its nitrogenized element. Oxygen p 
ates the protoplasm, but its affinity is resisted until vibratio®, a 
duced by some external irritation, aids its attractive energy: we 
the nitrogen molecule is attacked, and nitrogenized waste f a 
Urea is a constant product of muscle oxidation, and fe 
all oxidation of protoplasm, The denitrogenized remnant of — 
protoplasm remains in the cell. There are stored up, in © p 
