6a The Jrt of Farriery 



An Artery An Artery is a Conical Canal conveying the 

 dtlcnbcd. -^^r,^^ ^^Q^ fhe pj^^j.^ tQ j^ii p^rts of the Body. 



Each Arte ry is compofed of three Coat?, of which 

 the firft feems to be a Thread of fine Blood-Vefleb 

 and Nerves, for nourifhing the Coats of the Ar- 

 tery : The fecond is made up of Circular, or rather 

 Spiral Fibres, of which there are more or fewer 

 Strata or Coverings, according to the Bignefs of 

 the Artery. Thefe Fibres have a ftrong Elafticity, 

 by which they contrail themfelves with fome Force, 

 when the Power, by which they have been ftretch- 

 ed out, ceafes ,• in like Manner as a Piece of Cat- 

 Gut or Fiddle-String will do. The third and in- 

 moft Coat is a fine, denfe, tranfparent Membrane, 

 which keeps the Blood within its Canal, which 

 othcrwife, upon the Dilatation or ftretching out of 

 an Artery, would eafily feparate the Spiral Fibres 

 from one another. As the Arteries grow fmaller,, 

 thefe Coats grow thinner, and the Coats of the 

 Veins feem only to be Continuations of the Capil- 

 lary Arteries ; and are formed much thinner, be- 

 caufe that Strefs or Preffure of Blood does not lie 

 againll their Sides, as it does againft the Arteries. 

 And it is, as in this Particular, fo through the 

 whole Animal Machine that Nature has fhewn her 

 admirable Mechanifm and Workmanlhip : For if 

 the Arteries were not formed of fuch Conllrufture, 

 how much more incident would any Animal be 

 to dangerous Aneurifms or Over-llretching of the 

 Arteries ! This is fo plain, that I fcarce need in- 

 fill; upon it ; and I could give a Number of In- 

 ilances, where Men, as well as Horfes, have been 

 plunged into the difficult Cafe of an Aneurifm, 

 even by only wounding with a Lancet, or Fleam, 

 the outermoft Coat of an Artery : For by this un- 

 Ikilful Bleeding, the Coats (I mean the two found 

 Coats) are not able to refift thePulfition of the Ar- 

 tery, but are forced to yield and give Way ; fo that 

 in Proccfs of Time, the Tumour from Arterial 

 Blood will become as big as one's Head. The Cure 



of 



