IMPROVED. SS 



The Ufe of the Auricles is to receive the Blood, 

 which is brought by the Can;a and Fena Tuhnonalis, 

 and by them 'tis to be thruH forwards into the Ven- 

 tricles of the Heart. 



In the Heart there are two Cavities or Ventricles, 

 which anfwer to the two Ears, one on either Side; 

 the Sides of thefe Cavities are very unequal, fall of 

 Fibres and little flefny Produ<flions, long and round, 

 of a different Figure and Bignefs, called Columtue or 

 Pillars : Betwixt thefe Fibres there are feveral Fur- 

 rows in the Sides of the Ventricles, efpecially in the 

 left Ventricle, where they are deeper and longer. 

 They contribute much to the clofe Contradlion of 

 the Ventricles : And becam'e the Side of the right 

 Ventricle is much thinner than the left, therefore 

 there is often a fmall Bundle of Flefhy Fibres, which 

 come from the middle Partition, call'd by Anato- 

 mifls the Septum medium, to its oppofite Side, to 

 hinder it from dilating too much. 



The right Ventricle feems much wider than the Ths right 

 left, which is longer and narrower than the right, A'entricle 

 "and its Sides Wronger 2nd thicker^.and this. Nature •i^'^^'^^^'^d. 

 has contrived fo, becaufe it is the left Ventricle 

 which by Contra£lion throws the Blood all over the 

 Body. Therefore it was neceflary the Sides of it 

 fhould be much thicker and ftronger than thofe of 

 the right Ventricle. The two Ventricles are fepa- 

 rated by the Septum ?nedium, which is properly the 

 Infide of the left Ventricle, fmce its Fibres are con- 

 tinued or joined with the Fibres of the oppofite 

 Side of the fame Ventricle. 



The Veflels which enter, and come out of the its Vefftls. 

 Heart, are the Vena Ca^va, the Arteria, and Vena 

 Vulmonalisy and the Aorta or Arteria magna. 



The right Ventricle receives the Blood from the The right 

 Vena Ca-Da through the right Auricle or Ear, and VeritricJe of 

 at the Mouth of this Ventricle there are three J^^.^^^ft 

 Valves or Flaps made of a thin Membrane ; they ^^^^^^*'^"» 

 are of an Angular Figure, and called TricufpiJes ; 

 {heir Bafes are fixed to the Mouths of the Ventricles, 

 ^4 ^ 



