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Show Book III. De Cerebello. 103+ Thus having given a rough draught of the feveral Anfraé‘lm, Lionel/x, 0, Circles, lrocefses, Plexes of Arteries and Veins, attended with many this mite Glands ', as alfo the numerous ranks of nervous Fibres, branched in excellent order through the Cortical and Medullary Compage or the CmM lum. The life oFthe various parts otthc CereLII/Mm. I conceive it not amifs to finifh this rougher draught, in giVing you to change our Features into Smiles or Frowns, the pleafant or fer-ene expref- fesof Love and Anger. confil'ting in the procreation of the Animal Spirits, inadeot the more active and fpirituous parts of the Animal Liquor, the Vital Liquor being impelled out of the afcendent Trunk of the Aorta, into the vertebral Arteries, is conveyed out oftheir terminations into the fubfltance of the Glands, befetting the ambient parts of the Cerebellrtm, Where the delicate part ofrhe Blood is percolated from its more grols and fiery Particles, which are feparated and returned by the jugular Veins toward the Heart, While the roots of the Fibres implanted into the Cortex, and thence propagated by the fame continued Fibres into the Mctlnlla of the Cerebellnm, by whofe Prd ceflhs it is conveyed into the Nerves, derived from the Proteflim anmtldrir; and alfo by other Fibres communicated from the Cerebellztm to the Nerves of the Medal/,2 Spins/it, which is lodged within the Skull. Learned Dr. Willi; afligneth a peculiar Ofl-ice, diftinét from thatofrhe Brain to the Ccrcbcllum, to prelide and influence with Animal Spirits, the [othC temporal Mufcles Lips, and Tongue, which being rendred Tenfe With Animal Spirits, emitted from the Ccrebellum, can be diverfly contracted at our pleafure, in free acts of Maltication and Speaking; Thus having given an account of my firfi Hypotheiis, thatthe-Cerebellnm hath not altogether a Province difiinét from that of the Brain, in that the Cerebellnm is an Author ofvoluntary Motion, though in a lefs degree then that of the Brain : Now it may not be unfit to fpeak fomevvhat ofthe Second Hypothelis, that the Brain, and notthc Grebe/[um alone is the principle of involuntary aé‘tions, which I {hall endeavour to make good, by {hewrng how the Pulfation of the Heart, Refpiration and the like, involuntary aflions do proceed from the Brain. And Firl't as to the pulfation of the Heart,it is meetly an involuntary Motion, and the molt noble and neceiTary of all, upon which our Life doth immediately depend; and therefore it is molt wifely ordered by our Maker, That the Pulfation of the Heart. ihould not be controuled by our Will, lefi when we meet with fevere accidents we Iliould at cfle widelur Spirit!" Azzinmler not/0r [uppedz‘tdrc gin/2w: afiiuner int/0111mm"? m- the Heart. gunmr. Thefe involuntary Funt‘lions, he apprehended to be accompliihed by Nerves, acted by Animal Spirits fpringing from the (erebclium, by the interceflion of the Trottflitr ammlurir; New/i qnidam ( faith he) intuit/Jim a protubtrmztiiz rtmmluri, aliiq‘, in Witiflid oriumli, qui fmnfi‘ioni inmhtmarie a'efigmzti a (‘errbcllo Spirinumz A'niimzlizmz inflncntz‘do‘fitfczpimzt', This Opinion is involved, {as} humbly conceive) with great difficulties, ifnot improbabilities, which llhall endeavour to difcover, not out of any oppofition to this Learn- Cd Author (whofe memory I highly honour) but out ofa love of Tim, by proving Firlt that the Cerebellar»: hath not altogether a Province difiiné'f from that of the Brain, in that the Cerebtllnm is an Author of voluntary mo. tallcd the Drgaus ol'voluntary Motion. - once put a period to them and our Lives; and therefore the pulfation of the Heart is put out ofo'ur power, and derived from a fet and conflant influx of the Animal Spirits, conveyed for the mofi part, if not wholly from the Brain by the Tar wagum into the Fibres, feared in the Right and Left Chambers of jufmodi fum‘ Curclir pulflrtio, re/pz'rario, ratio 'dfimscg alimrnzi camoflia, (by/i prorrufio, b" [flit/Lt alzle (IMO 2101113; infeii/r, an! illvilif, cmflam‘i rilu firml, pm!- Ium, may he ~ . From the Fifth and Seventh pair of Nerves,are alfo imparted diverfe Branches Nerves configned to all involuntary Motions, and natural Aétions which he difcourfeth in the Fifteenth Chapter of his Book De (‘erclzri Anatome. {kind nempe Cerebellar}: fit Spiritumtz Animalium, in quad/ml opera defignatorm", peculiarir [wiurz‘go (9» perms ab ipfl: cerebro difliné-fur. Er Ccre/xclli afiiaitm hi DrJ'WliI Dirtrf'e pair of Nerves in the Cerebth derfianding, and commands ofthe Will, it beingin our pOWer, by the affiff. ance of thtfe pathetick Nerves, according to the impreflion of our phantaly it .- the chiefelt ( being that of the Cerebellum, common to it and the Brain) ous Particles, (commonly named the Animal Spirits) are tranfmitted into to be inimimvrytsnt'involuntary Motion. minute Mufcles of the Face. The motions. of thefe Mufclcs invigorated by Animal Spirits, conveyed by Nerves fptinging from the fProceflm annularis, the ol‘E‘ping of the Cerebellum, do Wholly comply .wrth the diétates of the un- Natures defign in framing this great variety, by fpeaking the feveral iifesof the more mild nutricious parts, impregnated With volatil Saline, and fpirim. The Her vrs of the Cerebellum allignrd M De Cerebello. Book Ill. tion as well as the Brain. And Secondly, the Brain and not the Cerebellum is the greater fountain of involuntary actions. As to the FirFt, it may be probably evinced, that the Cerebellar" is the principle of voluntary Actions in lbme degree, as well as the Brain; For the Fifth, Sixth, and Seventh pair ofNervcs (called by the former Anatomifts, the Third, Fourth, and Fifth pair) do proceed from the lid65 "Psi Bale Offl‘e Fratefll" ("Ni"lflyisa a part appendant to the t‘crcbellnm. Th6 l‘iifli pair perforating the Dam Mater, is divided into two eminent Trunks: the Firlt of which pai'iing in a [traight courfe, furnilheth the fmall Mufclesoi IhC FJCC With many confiderahle Fibres, which being varioufly contrafled and yelaxed, 590M116 thofe pathetick configurations, produced by the foft undurating motions of the Elevators, Adduétors, Abdufto"? ofthe l, ips, and other minute But this affertion meeteth with great oppofition from Dr. Willi/r, who referreth all unvoluntaryMotion, not to the Brain, but Cerebellum alone, as he ‘ molt plainly affirmeth in his Fifteenth Chapter De cerebrz Anatame, lmpmmr, ads/mi nerwmm paria quit fnnaionibm mmme trifling», out paflionnm zmpetu, potim quam arbitrii mun, obiri filitis, infirwiunt rte zmmedzfzte a Cerebello dependere, utfilummodo him in illarum origin" szrztmim Ammalmm mflnxm‘ deriwri o e wideatur. I cdhdbive this Hypothefis is involved with great difficulties, becaufe the motion of the Heart is not arbitrary, being celebrated by an inf'tmct of Nature, and yer doth not depend upon the Cerebellnm, as the only Origen, but upon the Brain as the greater fource of the Animal Spirits, becaufe the Sys hole in both chambers of the Heart, is produced prinCipally by .the Animal Spirits, communicated through a multiplicity of Fibres, fpringing from th; 1 q)" "Km", and inferred into the greatei't part of the Heart; wherefore the Syfiole {hould be caufed by the Animal Spirits, Howrng from the Cerebellum, it thould then be derived to the Heart by the Fifth, Sixth, or Seventh pair of Nerves, which take their Origen from the IPratubm‘mtm unnularir, a Procefs of [he Cerebellum, and not from the Eighth pair of Nerves; wit]. The Far vagum, which arifeth out ofthe {ides of the Mn: dulla oblanoam, a procefi; of the Brain, as Dr. Willis confefTet'h in hlS Twenty third Chapter De Cerebri Anatame. Ofiawn nerworitm wryngatw ab net-tire: aft‘"'i7"i-i PM fextrz babita, @ar wagum appellatur ; ztaque Infra tlimz,« , ., «:11 ntrworzim canjuqario e Iateribws Medullx oblangatx, malice rlyui Filn H (grwjriante, exoriiur. And firthet addeth, That a great PC; it 9 ~ The involuntary moiinn oFthe Heart, proceedtth from Nerves of the Brain. |