Page:Philosophical Transactions - Volume 002.djvu/226

 Printed or Manuscript, which latter were purposely searched after his death to find such a Discourse) our Author pretends, that that Proposition concerning the Infiniteness of the force of Percussion, not having been yet demonstrated by any, he hath in this Book resumed the whole matter concerning Percussion, and clearly demonstrated the true and genuine Nature of it, its Cause, Proprieties, and Effects. In the doing of which, he taketh occasion to discourse also of Gravity, Magnetism, Tremor of Bodies, Pendulums, &c. All which, whilst the Reader is considering, the Author tells him, that he is making ready his other Books concerning the Motions of Animals.

IV.  Florentiæ in 4. Ann. 1667.

The Author of this Book declareth, that his design in composing it was to shew, that in a Muscle neither the Parts of it can be distinctly named, nor its Motion duly considered, unless the Doctrine thereof become a part of the Mathematicks. And, he is of opinion, that there is no other cause of the many Errors, which spoil the History concerning the Humane Body, than that Anatomy hath hitherto disdain'd the Laws of the Mathematicks: And therefore inviteth those that are studious in that part of Philosophy, to consider, that our Body is an Engine made up of a thousand subordinate Engines, whose true knowledge whoever thinks that it can be investigated without Mathematical assistance, must also think, that there is matter without Extension, and Body without Figure.

Hereupon he shews, that the very Fabrick of the Muscles imposeth a kind of necessity upon considering Writers to explicate them Mathematically: in conformity whereunto, he pretends to have found, that in every Muscle there is one Parallelepiped of Flesh, and two Tetragonal Prisms of Tendons, defining a Muscle to be a Body composed of divers Series's, or ranks of Fibres, equal, like, and parallel among themselves, and so immediately placed upon one another, that whole Ranks are congruous to whole Ranks. Here he explains the Dimensions of a Muscle, its Contraction and Strength; and adds, that these of this new discovery of the structure of the Muscle, is to demonstrate, That they may swell in their Contraction without the Accession of new Matter.

He subjoins a Letter to Monsieur Thevenot, in which, among other things, he alledges several Experiments, to shew, that the motion of the Heart is like the motion of Muscles; and answers those who pretend, that the true Fabrick of the Heart hath already been observed heretofore; and those likewise who think, that these new Observations of the Muscles are uncertain, concluding this Subject with an enumeration of the Particulars, yet remaining to be be search'd into in the History of the Muscles.

To all these things he adds two Narratives; one, of a dissected Head of a Shark, which he calls Canis Carcharia, where he delivers many curious Observations of the Skin, Eye, Optick Nerves, Ocular Muscles, exceeding small-