Book IV. the Center of Motion and Strength. Likewife their various Form (34) in various Animals is confiderable, being all curioufly adapted to the peculiar Food (35) and Occafions of the feveral Species of Animals (36). And laftly, the temporary Defect of them (37) is no lefs obfervable in Children, and fuch young Creatures, where there is no occafion

(34) A curious Account of this may be found in an Extract of a Letter concerning the Teeth of divers. Animals. Printed at Paris, in M. Vaugnion's Compleat Body of Chirurg Oper. Chap 53.

(35) As it hath been taken notice of, that various Animals delight in various Food; fo it conftantly falls out, that their Teeth are accordingly fitted to their Food; the Rapacious to catching, holding and tearing their Prey; the Herbaceous to gathering and comminution of Vegetables: and fuch as have no Teeth, as Birds, their Bill, Craw and Gizard, are affifted with Stones, to fupply the defect of Teeth, But the moft confiderable Example of this kind is in fome Families of the Infect-Tribes, as the Papilio-kind, &c. who have Teeth, and are voracious, and live on tender Vegetables in their Nympha, or Caterpillar-ftate, when they can only creep; but in their mature Papilio-ftate, they have no Teeth, but a Probofcis, or Trunk to fuck up Honey, &c. their Parts for gathering Food, as well as their Food being changed, as foon as they have. Wings to enable them to fly to it.

(36) It is remarkable in the Teeth of Fishes, that in fome they are sharp, as allo jointed, fo as to fall back, the better to catch and hold their Prey, and to facilitate its Paffage into the Stomach: So in others they are broad and flat, made to break the Shells of Snails and Shell-fifh devoured by them. Thele Teeth, or Breakers, are placed, in fome, in the Mouth; in fome, in the Throat; and in Lobfters, &c. in the Stomach it felf; in the bottom of whofe Stomachs are three of thofe Grinders, with peculiar Mufcles to move them.

(37) What is there in the World can be called an A&t of Providence and Defign, if this temporary Defect of Teeth be not fuch; that Children, for inftance, fhould have none whilft they are not able to use them, but to hurt themselves, or the Mother; and that at the very Age when they can take in more fubftantial Food, and live without the Breaft, and begin to need Teeth, for the fake of Speech; that then I fay, their Teeth fhould begin to appear, and gradually grow, as they more and more fand in need of 'em.

(40)

(38)

cafion for them, but they would be rather an Annoyance to the tender Nipples and Breafts.

From the Teeth, the grand Inftruments of Maftication, let us proceed to the other minifterial Parts. And here the Parotid, Sublingual, and Maxillary Glands, together with thofe of the Cheeks and Lips are confiderable, all lodged in the molt convenient Places about the Mouth and Throat, to afford that noble digeftive falival Liquor, to be mixed with the Food in Maftication, and to moiften and lubricate the Paffages, to give an eafic defcent to the Food. The commodious Form alfo of the Jaws deferves our notice, together with the ftrong Articulation of the lowermoft, and its Motion. And lastly, the curious Form, the great Strength, the convenient Lodgment and Situation of the feveral Mufcles and Tendons (38), all miniftring to this fo neceffary an Act of Life, as Maftication is, they are fuch Contrivances, fuch Works, as plainly fet forth the infinite Workman's Care and Skill.

Next to the Mouth, the Gullet prefenteth it felf; in every Creature, well-fized to the Food it hath occafion to fwallow; in fome but narrow, in others as large and extenfive (39); in all exceedingly

(38) It would be endless to particularize here, and there fore I fhall refer to the Anatomifts; among the reft, parti cularly to Galen, for the fake of his Defeant upon this Subject. For having defcribed the great Accuracy of the Contri vance and Make of thefe Parts, he faith, Haud fcio an bomi num fit fobriorum ad Fortunam opificem id revocare: alioqui quid tandem erit, quod cum Providentia atque Arte efficitur? Omnino enim boc ei contrarium effe debet, quod cafu ac fortuitò fit, Galen de Uf. Part. 1. 11. c. 7. ubi plara.

(39) The Bore of the Gullet is not in all Creatures alike an fwerable to the Body or Stomach. As in the Fox, which both feeds on Bones, and swallows whole, or with little chewing; add next in a Dog, and other effivorous Quadrupeds, 'tis ve ry large, viz. to prevent a Contusion therein. Next in a Horse,

03

which

ingly remarkable for the curious Mechanim of

its Mufcles, and the artificial Decuffation and Pofition of their Fibres (40).

And now we are arrived to the grand Receptacle of the Food, the Stomach; for the most part as various as the Food to be conveyed therein. And here I might defcribe the admirable Mechahifm of its Tunicks, Mufcles, Glands, the Nerves, Arteries and Veins (41); all manifefting the fuper-eminent Contrivance and Art of the infinite Workman (42); they being all nicely adjusted to their refpective Place, Occafion and Service. I might alfo infift upon that moft neceffary Office of Digeftion; and here confider that wonderful Faculty

1

which though he feeds on Grafs, yet fwallows much at once, and fo requires a more open Paffage. But in a Sheep, Rabbit, or Ox, which bite fhort, and fwallow lefs at once, 'tis fmaller. But in a Squirrel, ftill leffer, both because he eats fine, and to keep him from difgorging his Meat upon his defcending Leaps. And fo in Rats and Mice, which often run along Walls with their Heads downwards. Dr. Grew's Comp. Anat. of Stom. and Guts. Chap. 5.

(49) Of this fee Dr. Willis's Pharm, Rat. Part 1, Sect. 1. c. 2. Steno alfo, and Peyer Mery. L. 2.

The Defcription thefe give of the mufcular part of the Guller, the late ingenious and learned Dr. Drake faith is very exa in Ruminants, but not in Men In Men, this

like two diftinet Mufcles, The outward being compofed of ftraight longitudinal Fibres.----The inner Order of Fibres is an nular without any obferveable Angles. The use of this Coat, and thefe Orders of Fibres is to promote Deglutition of which the Longitudinal,horten the Oefophagus, and fo make its Capacity larger, to admit of the Matter to be swallowed. The Annular, on the contrary, contract the Capacity, and closing behind the defcending Aliment, prefs it downwards. Drake's Anat. v, I. 1. 1. c. 9.

Coat [the fecond of the Gullet] confifts of two amella,

-741) See Willis, ibid Cowper's Anat. Tab. 35. and other Authors.

many

:(42) Proptuarium autem hoc, alimentum univerfum excipiens, ceu Divinum, non Humanum fit opificium. Galen de Uf. Part. 1. 4. c. T.

(43)

culty of the Stomachs of all Creatures, to dif folve (43) all the feveral forts of Food appropriated to their Species; even fometimes things of that confiftency as feem infoluble (44), efpecially by fuch seemingly fimple and weak Menftruums as we find in their Stomachs: But I fhall only give these things a bare mention, and take more peculiar Notice of the fpecial Provifion made in the particular Species of Animals, for the Digeftion of that special Food appointed them.

And in the first place it is obferveable, that, in every Species of Animals, the Strength and Size of their Stomach (45) is conformable to their

Food.

-(43) How great a Comprehenfion of the Nature of things, did it require, to make a Menftruum, that fbould corrode all forts of Flefb coming into the Stomach, and yet not the Stomach it felf, which is alfo Flesh? Dr. Grew's Cofmol, Sacr. c. 4.

(44) The Food of the Caftor being oftentimes, if not always dry things, and hard of Digeftion, fuch as the Roots and Bark of Trees, 'tis a wonderful Provifion made in that Creature's Stomach, by the digeftive Juice lodged in the curious little Cells there. A Defcription of whofe admira ble Structure and Order may be found in Blafius from Wepfer; concerning which he faith, In quibus Mucus reconditus, non fecus ac Mel in Favis. --- Nimirum quia Caftoris alimen tum exfuccum, & coctu difficillimum eft, fapientiffimus & fummè admirandus in fuis operibus rerum Conditor, D. Q.M. ipfi pulcherrima ifta & affabre facta ftructura benigniffimè profpexit, ut nunquam deeffet Fermentum, quod ad folvendum, & comminuendum alimentum durum & afperum par foret. Vid. Blaf. Anat. Animal, c. 10. Confer etiam A. Erud. Lipf, Ann, 1684. p. 360.

Most of our modern Anatomifts and Phyficians attribute Digeftion to a diffolving Menftruum; but Dr. Drake takes it to be rather from fermentative, diffolving Principles in the Aliment it felf, with the Concurrence of the Air and Heat of the Body; as in Dr. Papin's Digefter. Vid. Dr. Anat. L. C. 14,

(45) All carnivorous Quadrupeds have the smalleft Ventricles, Flefb going fartheft Thofe that feedon Fruits, and Roots, have them of a middle fize. Yet the Mole, because it feeds unclean, ath a very great one. Sheep and Oxen, which feed

Food. Such whofe Food is more delicate, tender, and nutritive, have commonly this Part thinner, weaker, and lefs bulky; whereas fuch whofe Aliment is lefs nutritive, or whofe Bodies require larger Supplies to answer to their Bulk, their Labours, and waste of Strength and Spirits, in them it is large and ftrong.

Another very remarkable thing in this Part is, the number of Ventricles in divers Creatures. In many but one; in fome two or more (46). In fuch as make a fufficient Comminution of the Food in the Mouth, one fuffices. But where Teeth are wanting, and the Food dry and hard (as in granivorous Birds) there the Defect is abundantly fupplied by one thin membranaceous Ventricle, to receive and moisten the Food, and another thick, ftrong, mufcular one, to grind and tear (47) it. But in fuch Birds, and other Creatures, whofe Food is not Grain, but Flesh, Fruits, InTects, or partly one, partly the other, there their Stomachs are accordingly conformable to their

Food

on Grass, have the greateft. Yet the Horfe (and for the fame, reafon the Coney and Hare) though Graminivorous, yet comparatively have but little ones. For that a Horfe is made for Labour, and both this, and the Hare, for quick and continued Motion; for which, the moft eafie Refpiration, and fo the freeft Motton of the Diaphragme is very requifite; which yet could not be, fhould the Stomach lie big and cumbersome upon it, as in Sheep and Oxen it doth, Grew, ib. Chap. 6.

(46) The Dromedary hath four Stomachs, one whereof is peculiarly endowed with about twenty Cavities, like Sacks, in all probability for the holding of Water. Concerning which, fee Book VI. Chap. 4. Note 1.

(47) To affift in which Office, they fwallow fmall angular Stones, which are to be met with in the Gizards of all gra nivorous Birds; but in the Gizard of the Fynx, or Wryneck, which was full only of Ants, I found not one Stone. So in that of the Green Wood-Pecker (full of Ants and Tree-mag gots) there were but few ftones.