Page:Philosophical Transactions - Volume 004.djvu/21

 the Place, than gives the Dimenlions of the Surfaces of the Solids of the Cycloid about the Base, it must be I, that must tell the World so; as well as the other Wonders of your New Analysis, and so many other things, which you have done me the honor to impart unto me, with that goodness you are pleas'd to have for me &c.

The Book here commended is the Second Edition of the Mesolabe of this Excellent Geometer, our Author; Concerning whose first Edition thus saith Stephano Angeli pag. 217. Accessionis ad Stercometriam & Mechanicen. Quomodo autem hujusmodi Problemata Solida construantur, edoctum fuit a quam plurimis; sed Herucleas metas in infinitum transcendit Nobilissimus & Clarissimus Geometra Renatus Franciscus Slusius Leodiensis in suo admirabili Mesolabo, in quo hæc infinitis enucleat modis.

Concerning this Book, we find it to be the judgement here, (and doubtless it will have the same esteem elsewhere among the Learned) that in it there is the most excellent Advancement made in this kind of Geometry, since the famous Mathematician and Philosopher Des Cartes.

He Learned Author of this Treatise (a Member of the R. Society) considering with himself, how important it was, for the arraigning a full knowledge of the Nature and Qualities of the Blood, to investigate, besides the Circular Motion thereof, the Origin and Celerity of that Motion, and the various Changes thereof, together with the Causes of them; as also, to make an estimate of the Quantity of that Liquor emitted at every Pulsation; thought it very well worth while, to give, from his own best Observations, a clear and particular account of that whole matter, And for as much as he conceives, that the Motion of the Blood depends on that of the Heart, he begins with a Discourse concerning the Situation and Structure of the Heart, to Rh