556 BIOLOGICAL PHYSICS 



proper, secretion, and excretion. Physiological chemistry 

 here works out, together with mechanical movement and 

 displacement, the complicated processes of tissue integra- 

 tion and disintegration by virtue of those affinities and 

 repulsions, so familiar to the students of matter directed 

 and determined by the dynamics of neural and general 

 life for vital, or organic, ends and purposes. 



Circulation, as thus observed in the adult organism, in 

 the sequence of its events, culminating in the metabolism of 

 the tissues, is carried on through a series of vascular media, 

 consisting of the alimentary canal, the chyliferous vessels, 

 the blood-vessels, systemic and pulmonary, arterial and 

 arterio-capillary, cellulo-osmotic and inter-cellulo-fibral, 

 or anabolic, the whole series terminating in the completed 

 metabolic or nutro-integrative, the latter dovetailing 

 with and beginning the katabolic or nutro-disintegrative, 

 consisting of the capillo-venous, the venous proper, 

 the lymphatic, dextro-cardial, and pulmonary. These 

 vascular, or circulatory, media consist of a graduated 

 series of organised vessels of definite lumina of separ- 

 ating and uniting membranes with meshes permeable by 

 osmosis and of connecting fibres -passable, or permeable^ 

 by the nutritive plasma, and its residual or waste material 

 results. 



The dynamics of highly organised forms of multi-cellular 

 life again emanate from, and are supplied and sustained, 

 uni- and multi-cellularly, by the two nervous systems the 

 sympathetic and the systemic, their manner of application 

 to the vital necessities of the living organism being known 

 by the name innervation. This innervation may either be 

 systemic or sympathetic, individual or conjoined, according 

 as the requirements of the body for the time being neces- 

 sitate, and there is also good reason for supposing that 

 nerve energy can be drawn simultaneously, when necessary, 

 from one or the other, or both, as local and general vital 

 requirements necessitate for the time being. 



Organic life is the peculiar field for the operation of 

 sympathetic innervation, while cerebral and cerebro-spinal 

 vital activity is the peculiar domain for the exercise of 

 systemic innervation, the former being uninterruptedly in 

 use from the beginning of life till its close, the latter only 



