QVEST. XXI. Of the Retention and Excretion of the Vrine, whether it be ac∣complished by a Natural or by an Animal faculty.
THE proper vse of the Bladder is to retayne the Vrine to a certaine time, and afterward to auoyde it; but by what power it doth this, Animall or Naturall, there lyes the controuersie. Some conceite that both the actions, as well * 1.1 the Retention as Expulsion are Naturall, because there is the same reason of both the bladders of gall and of vrine, but the bladder of gall reteineth and expelleth onely by the faculty which we call Naturall. Adde hereto that the triple kinde of fibres which are in both the bladders doe perswade vs that there is a threefold Naturall ac∣tion in them and not an Animall. On the contrary, it may bee demonstrated that both * 1.2 these actions are Animall on this manner. The Retention is made by Animal instruments, and therefore the action is Animall, this Animall instrument is a muscle. Now we know that the necke of the bladder is compassed about with a sphincter muscle, who playes the Porter and stoppeth the gate least the Vrine should passe away without our good plea∣sure.
That the Expulsion is Animal is witnessed as by other arguments, so by this, that accor∣ding to our arbitrary wil it is either flower or quicker, weaker or stronger, as also because it is not acomplished without the help of the muscles of the Abdomen. Galen in his first Book de locis affectis, and 6. Chapter, stinteth this strife, and sayth that the action is mixt; the Re∣tention, * 1.3 Animall, and voluntarie, as being performed by the helpe of a muscle, the Excre∣tian Naturall which is vndertaken and performed by the expulsiue faculty: For my owne * 1.4 part I thinke that both actions as well the Retention as the Expulsion, as partly Naturall & partly Animall, but the Retention more Animall, and the Expulsion more Naturall. The Vrine is retained in the bottom of the Bladder by the help of the oblique fibres; now that Retention is naturall; but beside it is retayned also at our pleasure by the helpe of the sphine∣ter muscle, and this action is meerely Animall. The vrine is Expelled by the ingenite po∣wer * 1.5 of the Bladder, whereby it is prouoked to auoyde that which is noysome or grieuous vnto it, & this Excretion is altogether Naturall. Again, the Vrine is Expelled at our plea∣sures by the help of the muscles of the Abdomen pressing the Hypogastrium or water-course; and some thinke that those small muscles of the Abdomen called Pyramidales or succenturi∣ati, that is, spirie or assistant muscles were ordained by Nature to further the excretion of this humour, and therefore both these actions are mixed.
Some will obiect that excretion can be no way naturall, because all naturall actions be∣ing perpetuall and indesinent the vrine should bee continually auoyded. Galen answereth * 1.6 that all vrine is not the obiect of the expulsiue faculty, but that onely which either fretteth or streatcheth, that is, which is offensiue either in quantity or in quality: and so much con∣cerning the Bladder; now follow the Paps.