Inquhy intojhe Nature a?id Properties of the Blood. 249 



fluidity. This more direct, more immediate, and proximate 

 cause of the blood's fluidity, it may seem at first sight diffi- 

 cult to demonstrate, as having apparently no real existence 

 in animal nature; but if the reality of things diminishes with 

 their invisibility to our eye-sight, or in proportion as they 

 evade our senses, it would be a fruitless effort to search the 

 finer textures and organizations of our bodies, — for in so doing 

 we should wander from the substance to the shadow : but if 

 on the contrary the reality of things increases with their im- 

 perceptibility to our senses, as is in truth the case ; if the finer 

 textures and organizations of our bodies astonish us by the 

 beauty, the simplicity, and the perfection of their forms, as in 

 truth they do ; we are labouring to a good purpose when we 

 are investigating them, we are tracing the direct path from 

 effects to causes, and proceeding by the method so insisted on 

 at the present day — of induction. 



Now, as the blood possesses all those elements which are 

 subservient to the building up the different textures of the 

 body from the cerebral to the osseous on the one hand, and 

 enjoys those properties and essentials which enable it to main- 

 tain its presence in and circulation through them on the other, 

 we are compelled to assent to the doctrine which teaches, or 

 which supposes, the permeability of the cerebral and nervous 

 textures, and their permeation by a subtile invisible fluid ; a 

 fluid not the less real for being invisible, nor the less material 

 for the want of tangibility ; a fluid that fulfils and accom- 

 plishes certain specific purposes and designs pre-eminently, — 

 which in relation to the solids and fluids is alone vital, which 

 builds up and compounds from its own elements the entire 

 cerebral and nervous textures, in the same manner as the red 

 blood furnishes the elements for the building up and com- 

 pounding the grosser vascular, fleshy, and bony textures : in 

 fine, a fluid which is every where present in the body, requi- 

 ring brain and nerves for its distribution, and red blood for 

 its seat and habitation*, imparting life at the same time to the 



cerebral 



* Wc hope to have it in our power to consider of the question of the 

 existence of a nervous fluid properly so called, and to discuss the f^rounds 

 for the objections which have been urged against the necessity or possi- 

 bility of its existence. We believe it vvould be just as rational to suppose 

 the phsenoniena of electricity could be presented in mundane natiu-e with- 

 out the medium of an appropriate nuindane agent, as that vital pli:cno- 

 mena could be presented in animal nature without the medium of their 

 appropriate animal agent. All qualities, attributes, forces, ])owcrs and modes, 

 must in the nature of things have their subjects in which they reside, ov 

 on which they depend : as for exani|)le, sound is a mode oi motion of the 

 air,and is dependent on air for its existence : the sensation it excites in the 



New Series. Vol. 2. No. 10. Oct. 1827. 2 K '^^°'"" 



