Page:Cyclopaedia, Chambers - Volume 1.djvu/581

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DIG

[215]

DIG

Sorel'ii

on the footing of the Equilibrium of Fluids, while it goes on. The Iron, Needles, Pins, iSc. fometimeS

found undiffolved in the Stomai '

Syftem of Fermentation; it being notorious, that no Diffol- vent diffolvcs all Bodies. In Birds, which feed on Grain, the Fermentation is raanifeft, firft, in the Crop where the Grain is prepar'd for Digefiion, by being macerated in a Liquor like Saliva; and afterwards in the Gizzard, where the Digefiion is perfected by a Diffolvent pour'd into it by a

J j'gmonftrated, that the Force of the Flexor of the loft found undiffolved in the Stomach, are no Objection to the. 4 riculation of the Thumb is equal to 3720 Pounds : Whence " 1 Uu-airtt deduces, that the Force of the Fibres of the Stomach • oual to 12951, and that of the Diaphragm, and Mufcles of he lower "Venter, to 248235 Pounds. His Way of Eftimating

s -The Flexor only weighs 122 Grains, and yet may J s „ a j n '. 7 2oPounds: Confequently, the Fibres of the Stomacli

, Grains,

-'(ihin'a 8 Ounces, and the Diaphragm with the Mufcles of conglomerate Gland. But the Thing is ftifl more apparent in Slower Venter, weighing together 8223 Grains, have the Ruminating Animals, which are provided with tour Sto- L lu a bovemention'd. But this Argumentation feems machs; the two firft whereof, tho' form'd of a nervous f "unded on a Miftake; for 'tis not in Virtue of its Weight of Membrane, make but little Alteration in the Aliment, for

~ Want of a Ferment, or Menfinmm; So that it returns to be chew'd again; and only becomes well digefled in the fourth Stomach, whither a Diffolvent is pour'd from a conglome- rate Gland.

The Partifans of the third Opinion allow it inconteftable, that there are Acids in the Stomach, which mix with the Foods, and act on them; and hold likewife, that their Ac- tion is aided, and promoted by the Motion of the Syftolc, and Diaftole in the Vifcera : They add, that the Acids . produce a Fermentation; and the Ofcillatory Motion of the cdver' ° r Vat. They contend, that Cafiellus, a Phyfician of Vifcera a Trituration; and that thus Digefiion is the Ef- fect of Fermentation, and Trituration at the fame Time.

Be it as it will with each of the threeSyftems; thus much we may venture to lay down from 'em all, as the real Procefs ^Di- gefiion: The End of this Operation being to prepare the Foods, to as they may ferve for Nutrition; thole Foods muft be confi-

that the Flexor Mufcle is equivalent to 37 Pounds : Befides that it would follow hence, that the hea- ler the Mufcles of the Stomach, Diaphragm, and Abdo- men are, the more Force they would have, and confequent- ly the more cafy, and expedite would the Digefiion be : V vhich is falfe. _

The Patrons of this Syftem compare the Brain to the Arbor, or Screw of a Prefs, the Heart to a Pifton, the Lungs to Bellows, the Mouth to a Mill-ftone or Pcflle, the Stomach to a Prefs, and the Inteftines to a Re

' or Vat. They contend, that Cafiellus, flfcfljna, was the firft of the Moderns, who exprefsly efpou fed the Syftem of Ferments, and that he was followed by Via Helmonr, and Willis.

But even the Partifans of Trituration are not perfectly agreed among thcmfelves : 'Pitcairn will have it perform'd

by a total Contracf ion of the Stomach : And Mr. Hecquet, der'd from the Time the Man takes them in, till being converted

by a fucceflive, periftaltic, or vermicular Contraction. into Chyle, they mix with the Blood, which conveys them into

JJlriic, in his Treatife, de la Caufe de la Digefiion, re- all Parts of the Body. The Foods then we take, are cither

futes this Syftem of Trituration at length. He makes a crude, as Oifters, Fruits, certain Pulfe, ci?c. or drefs'd, as Flefhv

ftrong Oppofition to the Calculus, which raifes the moving and Fifli, which are roafted, boil'd, fried, i£c. and fcafon'd a

Force of the Stomach, £SV. fo very high. The Contraction thoufand divers Ways with Salt, Pepper, and other Spices,

of the Fibres of the Stomach, to comprefs the Food, he Vinegar, Wine, £?c. to heighten and enrich the Tatte as

Ihews, cannot exceed three Ounces; and 'tis even gratis that much as to aflift Digefiion. See Food, Dressing, tSc. he allows fo much : That of the Diaphragm, and Abdomen.

he computes at about 4 Pounds. He obferves, that <Pitcairn K furprized, in all Probability, with what he had affcrted of this Force, durft not puriue the Proportion whereon his Cal- culus was founded, and according to which, one of the Forces would be found equivalent to 117088 Pounds, and the other to 250734; which together make 357822 Pounds. The

Further, there are fome Foods we fwallow without chew- ing, as Liquids; and others, which we break and commi- nute by chewing, as Bread, Flefli, ci?c. 'Tis of thefe laft we ftiall here fpeak, as undergoing more Preparations, and more Changes to fit them for Food, than the others.

The Food, then, is firft broke, and divided by the Teeth, and, at the fame Time, moiftcn'd with a Liquor fup- Diaphragm in its Motion has two Forces; the one direct, plied by the Salival Glands, and thus form'd into a Kind of which is that, whereby its Mufcles draw from the Centre to Pafte. See Mastication.

the Circumference : the other lateral, whereby it refts, or Thus prepar'd, it is pafs'd through the Oefophagus into preffes on the Stomach; The latter very fmall in Compari- the Stomach, there to ferment. Sec Deglutition. ion of the former. Now, what has deceiv'd Mefs. <Pitcairn This Fermentation is caufed, 1. By theSalival Juice, which: and Hecquet, is, their taking the direct for the lateral Force; is a Ferment, and has the fame Eftect on the Aliment, that the Contraction of Fibres for their Preffure on the Stomach. Leaven, or Barm has on Pafte. 2. By the Heat of the Sto- And the fame Overfight they are guilty of in the Mufcles m ach, Vifcera of the Abdomen, and e ven Excrements j which of the Abdomen, whofe Prefiure againft the Abdomen is here has nearly the fame Effect on Foods, as the Dunghill has only lateral Add, that there are voracious Animals with- on Matters laid by theChymifts to digefi therein. 3. By the_ out any Diaphragm at all; as Fifties, which refpire through Remains of Foods left adhering in the Rug<e, or Folds of their Gills : and others that have only a tingle Membrane; as the Stomach, and there turn'd lour, and acrimonious. 4. By Birds in whom the Mufcles of the lower Venter are very the Compreflion of the Mufcles ot the Abdomen, and Dia- fmall' and feeble, and in a Situation that incapacitates them phragm. 5. By the Liquor which the repeated Compreflion

of thofe Mufcles occafions to drip from the Glands of the Stomach. 6. According to the Sentiment of fome modern Phyficians, by the Air it felf, which b;ing mix'd, and em- barafs'd in the Aliments, dilates by the Heat of the Stomach, and feparates rhe Parts of the Foods. Thefe Caufes all con- tribute to attenuate, and divide the Food, fo as to convert them into a cineritious Matter, cM'd Chyle. See Chyle.

From rhe Stomach the Chyle defcends into the Ducode- num, where it is further pcrtecfed by the Pancreatic Juice, and the Bile, which thin it, precipitate its gruffer Parts, and render it more fluid. The Chyle thus perfected and attenua- ted, enters the Lacteal Veins, which convey it into the Receptacle, where it is further diluted by the Lymfha, which is brought hither in Abundance. Hence it rifes into the Tho- racic Duel:, and enters the Subclavian Vein; where being taken up by the afcending Cava, it is pour'd into the right

from acting at all on the Stomach.

The Membranes of the Stomach being very foft, and ha- ving only a ilendcr Motion, feem very unfit for the Office of a Mill-ftone. 'Tis true, in certain Fowls the Stomach con- fifts of a clofe, compact, fleftiy Mufcle exceeding ftrong, fo as to break little Stones, and Bits of Glafs. But to this it is umed that it is no Digefiion, which in thefe Animals is effected in the Inteftines. And the Struflure of our Stomach compared with the Gizzard, or Crop of granivorous Birds, does, on the contrary, furnifti a very cogent Argument againft Trituration. The Gizzard is provided on the Out-fide with four fleftiy Mufcles, the Tendons whereof meet in two oppo- fite Points : The Infidc is lined with a hard, thick, cartila- genous Membrane; efpecially in the Places where the Tendons meet. By this Mechanifm Nature plainly intimates the Of- fice of the Gizzard to be the Grinding of the Grain by the

FriaionofitsParietcs, or Sides: Whereas, the Membrane in Ventricle ot the Heart, the Stomach of a Man is exceedingly thin and fine, furmftl'd The Chyle thus mixing with the Blood, embaraffs the with a few fleftiy Fibres cover'd with a tender, fenfible Kind Globules thereof, and thus abates its Motion: And hence of Down; and the Stomach it felf is of a grear Capacity, thattalination to go to fleep after Meals. But, by Degrees, And the Stomach in rapacious Birds, who devour huge Pieces ofrawFlefti without chewing, is a ftill finer Membrane.

Laftly, on the Syftem of Trituration there feems no accounting for Hunger, Naufea's, Indigeftions, Crudities, Ot.

the Blood communicates its Motion to the Chyle; and by its volatile, and exalted Parts, together with the Saline and Nitrous Parts of the Air, fubtilizes, and gives it its laft Per- feflion. Then the Digefiion is finiih'd : and the Foods being

In the Syftem of Trituration it feems impoffible to explain, by fo many Changes render'd the immediate Matter >ol is u-

why certain Things eafy to grind, e.gr. Cabbage Flowers, can- tntion, are carried by the Blood mg) all Farts ottnecqay

JtotbeSw in certain Stomachs^ which y« find no Dim- to repair, and fill the Vacancies ot fuch as are com nttally

tulty i„ djgefiing more hard, and folid Meats, as Beef, and diffipating, and exhaling; or even to add new ones, etc jsb-

Mutton: Whereas, the Difference of Diffolvcnts gives ana- trition fo,,„ted from the

Hydropic People continue to digefi, ^ As to the groffer Parts of the Foods

tural, and eafv Solution, tlyciropic I'eopie luuuh^ ■•« «"&<.r, » B iumu**.« "■—:--. 1 /■-

notwithftandJg the Fibres of the Stomach, as well as the Chyle by the Bile »d Jtereanc Ju.ee ^hey affum^the to

'd through the Abun- lour of Excrements from the Bne; and that rank Smell, tney

■-- thereof. Thefe Sulphurs, erve, after they have palled

reft of the Body, arc cxtreamly rclax'c .-

dance of Humour. And the total, prompt Change of Na- derive from the coarfer Sulphurs tefl of nothing clfc but .and Salts of the Excrements, let

ture induced in Foods can be the Effect of nothing

Fermentation; which even difcovers it felf by Belches, t?c. through the Inteftines,

and are arrived at the laft, which is the