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XXXVI. Outlines of a Philosophical Inqxdry into the Nature 

 and Properties of the Blood; being the Substance of three 

 Lectures on that Subject delivered at the Gresham Institution 

 during Michaelmas Term 1826. By John Spurgin, M.D. 

 Fellow of the Roijal College of Physicians of London, and of 

 the Cambridge Philosophical Society. 



[Continued from vol. i. p. 426.] 



"C'LUIDITY is a property of the blood which is next to 

 -*- vitahty in importance; and indeed it may be rej^arded as 

 the second essential of its nature, fitting or adapting it to fulfil 

 the purposes of its first essential, — Vitality. From all that we 

 have advanced upon the composition of the blood, it may be 

 seen that this property is modified or affected by manifold 

 circumstances ; by none, however, more than by withdrawing 

 it from its native vessel and keeping it at rest ; when it soon 

 enters upon another kind of existence, intermediate, as it 

 were, between fluidity and solidity, assuming the form and 

 state of a soft solid by accomplishing its tendency to coagula- 

 tion. But in order to comprehend the great importance of 

 this property of the blood, (viz. its fluidity,) we must first ex- 

 press the notion we entertain respecting the term Vitality. The 

 coagulation of the blood has been regarded as the last effect 

 of its vitality, and as the best proof of its possessing life, inas- 

 much as in this respect it approximates to the condition of the 

 solids of the body, which are considered to be undeniably vi- 

 tal, by reason of their exhibiting the undoubted marks of life 



Contractility and Sensibility. But if these be the only leo-iti- 

 mate marks and signs of the presence of life, — the only phse- 

 nomena that are essentially vital, — such a proof as the above is 

 extremely detective, if not highly fallacious; for whilst the co- 

 agulating blood exhibits no marks whatever of sensibility, its 

 properties agree in nothing with contractility. Coagulation and 

 contraction are terms applicable to two differentkinds of matter. 

 Coiigulation applies to the solidifying of fluids, Contraction to 

 the dimininished volume of solids: the coagulation of the 

 blood, therefore, has nothing to do with the contraction of a 

 muscle ; nor the fibrillary structure of coagulated blood with 

 muscular structure : in the former, moreover, the arrano-ement 

 of the fibres is reticular or plexiform ; in the latlei-, longitu- 

 dinal only, and this most distinctly so; each fibre being kejit 

 separate i'rom its neighbour by an investing sheath. 



What are we to understand by the term Vitality ? Is it a pro- 

 perty of matter? of the blood for example; or is it something 

 superadded to matter ? to the blood, for example ; or is it a term 



signifying 



