THEORY OF ONE ONLY LIVING MATTER. 9 



irritability or vitality to those peculiar aggregations of 

 matter which go to form respectively the cellular, 

 dermoid, mucous, serous, vascular, fibrous, osseous, car- 

 tilaginous, or muscular tissues," and also to the white 

 matter of the nerves. Thus every one of the struc- 

 tures possessing any degree of rigidity, usually de- 

 nominated the living tissues, is in reality dead just 

 as much as cuticle, hair, nails, and all the pure fluids. 



.The only truly living matter consists of the gray^l 

 matter of the ganglionie nerves, which he held to be ^ 

 universally diffused, and the gray matter of the brain / 

 and spinal marrow. 



The physical and chemical description of this one 

 true and only living matter is that of " a pulpy, trans- 

 lucent, homogeneous matter, yielding, after death, 

 fibrin." Thus we have the remarkable conclusion 



/that all that is properly called structure and gives 

 form and beauty and fitness for purpose to animals 



I and plants is dead, and composed of merely chemically 

 combined elements, just as we find it after death. 

 Here then is an ample field for the display of those 

 mechanical and chemical actions, which are certainly 

 largely represented in the functions of living beings, 

 without trenching on the truly vital actions. We may, 

 without difficulty, now perceive how the bones give 

 firmness and support ; how the teeth grind the hardest 

 substances ; how the arteries and veins form a perfect 

 system of conduits for nutrient fluid ; how the fibrous, 

 elastic, and connective tissues perform their respective 

 physical functions; how the muscles form an appa- 

 ratus, admirably adapted for the physical conditions of 

 motion in a particular direction, while a purely vital 



