I'

CHA P. II.

Of the Heads of QUARDUPEDS.

T is remarkable, that in Man, the Head is of one fingular Form; in the four-footed Race, as various as their Species. In fome fquare and large, fuitable to their flow Motion, Food, and Abode; in others lefs, flender, and sharp, agreeable to their swifter Motion, or to make their Way to their Food (a), or Habitation under Ground (b). But paffing by a great many Obfervations that might be made of this Kind, I fhall ftop a little ar the Brain, as the most confiderable Part of this part of the Body, being the great Inftrument of Life and Motion in Quadrupeds, as 'tis in Man of that, as alfo in all Probability the chief Seat of his immortal Soul. And accordingly it is a remarkable Difference, that in Man the Brain is large, affording Substance and Room for fo noble a Gueft; whereas in Quadrupeds, it is but small. And another Thing no lefs remarkable, is the Situation of the Cerebrum and Cerebellum, or the greater or leffer Brain, which I fhall give in the Words of one of the most exact Anatomifts we have of that

(a) Thus Swine, for Inftance, who dig in the Earth for Roots and other Food, have their Neck, and all Parts of their Head very well adapted to that Service. Their Neck fhort, brawny, and ftrong; their Eyes fet pretty high out of the Way; their Snout long; their Nofe callous and strong; and their Senfe of Smelling very accurate, to hunt out and diftinguish their Food in Mud, under Ground, and other the like Places where it lies concealed.

(b) What hath been faid of Swine is no lefs, rather more remarkable in the Mole, whofe Neck, Nofe, Eyes and Ears, are all fitted in the niceft Manner to its fubterraneous Way of Life.

Part (Since, faith he, God hath given 66 to Man a lofty, Countenance, to behold the "Heavens, and Hath alfo feated an immortal Soul "in the Brain, capable of the Contemplation of "heavenly Things; therefore, as his Face is erect, "fo the Brain is fet in an higher Place, namely, "above the Cerebellum and all the Senfòries. But "in Brutes, whofe Face' is prone towards the "Earth, and whofe Brain is capable of Specula. “ tion, the Cerebellum, (whofe Business it is to minifter to the Actions and Functions of the "Præcordia, the principal Office in thofe Crea"tures) in them is fituated in the higher Place, " and the Cerebrum lower. Alfo fome of the Or .co gans of Senfe, as the Ears and Eyes, are placed, "if not above the Cerebrum, yet at least equal thereto.

Another Convenience in this Pofition of the Cerebram and Cerebellum, the laft ingenious Anatomift (d) tells us is this, "In the Head of Man,

faith he, the Bafe of the Brain and Cerebell, yea, "of the whole Skull, is fet parallel to the Hori"zon; by which Means there is the lefs Danger of "the two Brains joggling, or flipping out of their "Place. But in Quadrupeds, whofe Head hangs "down, the Bafe of the Skull makes a right An"gle with the Horizon, by which Means the Brain "is undermoft, and the Cerebell uppermoft; fo "that one would be apt to imagine the Cerebell "fhould not be fteady, but joggle out of its "Place. To remedy which Inconvenience he "tells us, And left the frequent Concuffions of "the Cerebell fhould cause a Fainting, or diforder

(c) Willis Cereb. Anat. cap. 6. Cumque huic Deus os fublime dederit, &c.

(d) Id. paulo poft. In capite humano Cerebri & Cerebelli, &c. "ly

"ly Motion of the Spirits about the Precordia, "therefore, by the Artifice of Nature, fufficient "Provifion is made in all, by the dura Meninx "closely encompaffing the Cerebellum; befides “which, it is (in fome) guarded with a strong "bony Fence; and in others, as the Hare, the "the Coney, and fuch leffer Quadrupeds, a part "of the Cerebell is on each Side fenced with the "Os Petrofum: So that by this double Stay, its "whole Mass is firmly contained within the Skull.

Befides these Peculiarities, I might take notice of divers other Things no lefs remarkable, as the Nictitating Membrane of the Eye (e), the different Paffages of the Carotid Arteries (f) through the

(e) See Book IV. Ch. 2. Note (kk).

(f) Arteria Carotis Aliquanto pofterius in homine quàm in alio quovis animali, Calvariam ingreditur, fcil. juxta illud foramen, per quod finus lateralis in Venam jugularem defiturus cranio elabitur; nam in cateris hac arteria fub extremitate, feu proceffu acuto offis petrofi, inter cranium emergit: verùm in capite humano, eadem, ambage longiori circumducta (ut fanguinis torrens, priufquam ad cerebri oram appellit, fracto impetu, lenius placidius fluat) prope fpecum ab ingreffu finûs lateralis factum, Calvaria bafin attingit; in majorem

cautelam, tunica infuper afcititia craffiore inveftitur. And fo he goes on to fhew the Conveniency of this Guard the Artery hath, and its Paffage to the Brain, and then faith, Si hujufmodi conformationis ratio inquiritur, facilè occurrit, in capite humano, ubi generofi affectus & magni animorum impetus ac ardores excitantur, fanguinis in Cerebri oras appulfum debere effe liberum & expeditum, &c. Atque hoc quidem refpectu differt Homo à plerifque Brutis, quibus, Arteria in mille furculos divifa, ne fanguinem pleniore alveo, aut citatiore, quàm par eft, curfu, ad cerebrum evehat, Plexus Retiformes conftituit, quibus nempe efficitur, ut fanguis tardo admodum, lenique & aquabili fere ftillicidio, in cerebrum illabatur. And then he goes on to give a farther Account of this Arsery, and the Rete mirabile in divers Creatures. Willis, ibid. cap. 8.

Skull, their Branching into the Rete Mirabile (g), the different Magnitude of the Nates, and fome other Parts of the Brain in Beafts, quite different from what it is in Man: But the Touches already given, may be Inftances fufficient to prevent my being tedious in inlarging upon thefe admirable Works of God.

(g) Galen thinks the Rete mirabile is for concocting and elaborating the Animal Spirits, as the Epididymides, [the Convolutions goods aix] are for elaborating the Seed. De Uf. Part. L. 9. c. 4. This Rete is much more confpicuous in Beafts than Man; and as Dr. Willis well judges, ferves, 1. To bridle the too. rapid. Incurfion of the Blood into the Brain of thofe Creatures, whofe Heads hang down much. 2. To feparate fome of the fuperfluous ferous Parts of the Blood, and fend them to the Salival Glands, before the Blood enters the Brain of thofe Animals, whofe Blood is naturally of a watery Conftitution., 3. To obviate any Obftructions that may happen in the Arteries, by giving a free Pallage through other Veffels, when fome are ftopped.

In Quadrupeds, as the Carotid Arteries are branched into the Rete Mirabile, for the bridling the too rapid Current of Blood into the Brain; fo the Vertebral Arteries, are, near their Entrance into the Skull, bent into an acuter Angle than in Man, which is a wife Provifion for the fame Purpofe.

ROM the Head pafs we to the Neck, no prins

Fcipal Part of the Body, but yet a good In

ftance of the Creator's Wisdom and Defign, inafmuch as in Man it is fhort, agreable to the Erection of his Body; but in the Four-footed Tribe it is long, anfwerable to the Length of the

Legs

Legs (a), and in fome of these long, and less strong, ferving to carry the Mouth to the Ground; in others shorter, brawny and ftrong, ferving to dig, and heave up great Burdens (b).

But that which deferves efpecial Remark, is that peculiar Provifion made in the Necks of all, or most granivorous Quadrupeds, for the perpetual holding down their Head in gathering their Food, by that ftrong, tendinous and infenfible Aponeurofis, or Ligament (c) braced from the Head to the middle of the Back. By which means the Head, although heavy, may be long held down without any Labour, Pain, or Uneafinefs to the Mufcles of the

.

(a) It is very remarkable, that in all the Species of Quadrupeds, this Equality holds, except only the Elephant; and that there should be a fufficient special Provifion made for that Creature, by its Probofcis or Trunk. A Member fo admirably contrived, fo curioufly wrought, and with so great Agility and Readinefs, applied by that unweildy Creature to all its feveral Occafions, that I take it to be a manifeft Inftance of the Creator's Workmanship. See its Anatomy in Dr. A. Moulen's Anat. of the Elephant, p. 33. As alfo in Mr. Blair's Account in Phil. Trans. No. 326.

Ma

Aliorum ea eft humilitas ut cibum terreftrem roftris facilè contingant. Qua autem altiora funt, ut Anferes, ut Cygni, ut Grues, ut Cameli, adjuvantur proceritate collorum. nus etiam data Elephantis, qui propter magnitudinem corporis difficiles aditus habebant ad pastum. Cic. de N. D. L. 2. c. 47.

Quod iis animalibus qua pedes habent fiffos in digitos, Collum brevius fit factum, quàm ut per ipfum Cibum ori admovere queant: iis verò que ungulas habent folidas, aut bifidas, longius, ut prona atque inclinantia pafci queant. Qui id etiam opus non fit Artificis utilitatis memoris ? Ad hac quòd Grues ac Ciconia, cùm crura haberent longiora, ob eam caufam Roftrum etiam magnum, & Collum longius habuerint. Pifces autem neque. Collum penitus habuere, utpote qui neque Crura habent. Quo pacto non id etiam eft admirandum? Galen.de Uf. part. L. 11. c. 8.

(b) As in Moles and Swine, in Ch. 2. Note (a).

(c) Called the Whiteleather, Packwax, Taxwax, and Fix

fax.

Y 2

Neck,