Zoonomia, Vol. I, by Erasmus Darwin potx

XXIX.The Retrograde Motions of the Absorbent Vessels.. The secondary motions arethose, which are given to or received fromother matter in motion.. divided into three classes, those belon

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Title: Zoonomia, Vol I

Or, the Laws of Organic Life

Author: Erasmus Darwin

Release Date: April 25, 2005 [EBook

#15707]

Language: English

*** START OF THIS PROJECT GUTENBERG EBOOK

OF

ORGANIC LIFE.

VOL I.

By ERASMUS DARWIN,

M.D F.R.S.

AUTHOR OF THE BOTANIC GARDEN

Principiò cœlum, ac terras,

camposque liquentes,Lucentemque globum lunæ,

titaniaque astra,

Spiritus intùs alit, totamque

infusa per artus

Mens agitat molem, et magno

se corpore miscet.—VIRG Æn vi

Earth, on whose lap a

thousand nationstread,

And Ocean, brooding his

prolific bed,

Night's changeful orb, blue

pole, and silveryzones,

Where other worlds encircle

other suns,

One Mind inhabits, one

diffusive Soul

Wields the large limbs, and

mingles with thewhole

THE SECOND EDITION,

Entered at Stationers' Hall.

DEDICATION.

To the candid and ingenious Members ofthe College of Physicians, of the RoyalPhilosophical Society, of the TwoUniversities, and to all those, who studythe Operations of the Mind as a Science,

or who practice Medicine as a Profession,the subsequent Work is, with greatrespect, inscribed by the Author,

DERBY, May 1, 1794

Preface.

SECT I Of Motion.

II Explanations and Definitions.

III.The Motions of the Retina

demonstrated by Experiments.

IV Laws of Animal Causation.

V.Of the four Faculties or

Motions of the Sensorium.

VI.Of the four Classes of Fibrous

Motions.

VII Of Irritative Motions.

VIII Of Sensitive Motions.

IX Of Voluntary Motions.

X Of Associate Motions.

XI Additional Observations on

the Sensorial Powers.

XII

Of Stimulus, Sensorial Exertion, and Fibrous Contraction.

XIII Of Vegetable Animation.

XIV Of the Production of Ideas.

XV Of the Classes of Ideas.

XXIII Of the Circulatory System.

XXIV

Of the Secretion of Saliva, and of Tears And of the

Lacrymal Sack.

XXV Of the Stomach and Intestines.

XXVI.Of the Capillary Glands, and

of the Membranes.

XXVII Of Hemorrhages.

XXVIII The Paralysis of the Lacteals.

XXIX.The Retrograde Motions of

the Absorbent Vessels.

XXX The Paralysis of the Liver.

XXXVI The Periods of Diseases.

XXXVII.Of Digestion, Secretion,

Nutrition.

XXXVIII

Of the Oxygenation of the Blood in the Lungs and Placenta.

By DEWHURST

BILSBORROW.

HAIL TO THE BARD! who sung,

from Chaos hurl'd

How suns and planets form'd the

unfinish'd laves,

Sips with rude mouth the salutary

waves;

Seeks round its cell the sanguine

streams, that pass,

And drinks with crimson gills the

eyelid hails,

With lungs untaught arrests the balmy

gales;

Tries its new tongue in tones

unknown, and hears

The strange vibrations with

And learns erelong, the perfect form

How thoughts to thoughts are link'd

with viewless chains,

Tribes leading tribes, and trains

pursuing trains;

With shadowy trident how Volition

—So saw the Patriarch with admiring

eyesFrom earth to heaven a golden ladder

rise;

Involv'd in clouds the mystic scale

ascends,And brutes and angels crowd the

distant ends

TRIN COL CAMBRIDGE, Jan 1, 1794.

REFERENCES TO THE WORK.

Part I

The purport of the following pages is anendeavour to reduce the facts belonging toANIMAL LIFE into classes, orders,genera, and species; and, by comparingthem with each other, to unravel the theory

of diseases It happened, perhapsunfortunately for the inquirers into theknowledge of diseases, that other scienceshad received improvement previous totheir own; whence, instead of comparingthe properties belonging to animatednature with each other, they, idly

ingenious, busied themselves in attempting

to explain the laws of life by those ofmechanism and chemistry; they consideredthe body as an hydraulic machine, and thefluids as passing through a series ofchemical changes, forgetting thatanimation was its essential characteristic.The great CREATOR of all things hasinfinitely diversified the works of hishands, but has at the same time stamped acertain similitude on the features of nature,

that demonstrates to us, that the whole is

one family of one parent On this

similitude is founded all rational analogy;which, so long as it is concerned incomparing the essential properties ofbodies, leads us to many and importantdiscoveries; but when with licentious

activity it links together objects, otherwisediscordant, by some fanciful similitude; itmay indeed collect ornaments for wit andpoetry, but philosophy and truth recoilfrom its combinations.

The want of a theory, deduced from suchstrict analogy, to conduct the practice ofmedicine is lamented by its professors;for, as a great number of unconnected factsare difficult to be acquired, and to bereasoned from, the art of medicine is inmany instances less efficacious under thedirection of its wisest practitioners; and

by that busy crowd, who either boldlywade in darkness, or are led into endlesserror by the glare of false theory, it isdaily practised to the destruction ofthousands; add to this the unceasing injury

which accrues to the public by theperpetual advertisements of pretendednostrums; the minds of the indolentbecome superstitiously fearful of diseases,which they do not labour under; and thusbecome the daily prey of some craftyempyric.

A theory founded upon nature, that shouldbind together the scattered facts ofmedical knowledge, and converge intoone point of view the laws of organic life,would thus on many accounts contribute tothe interest of society It would capacitatemen of moderate abilities to practise theart of healing with real advantage to thepublic; it would enable every one ofliterary acquirements to distinguish thegenuine disciples of medicine from those

of boastful effrontery, or of wily address;and would teach mankind in some

important situations the knowledge of

themselves.

There are some modern practitioners, whodeclaim against medical theory in general,not considering that to think is to theorize;and that no one can direct a method ofcure to a person labouring under diseasewithout thinking, that is, withouttheorizing; and happy therefore is thepatient, whose physician possesses thebest theory

The words idea, perception, sensation,recollection, suggestion, and association,are each of them used in this treatise in amore limited sense than in the writers ofmetaphysic The author was in doubt,

whether he should rather have substitutednew words instead of them; but was atlength of opinion, that new definitions ofwords already in use would be lessburthensome to the memory of the reader.

A great part of this work has lain by thewriter above twenty years, as some of hisfriends can testify: he had hoped byfrequent revision to have made it moreworthy the acceptance of the public; thishowever his other perpetual occupationshave in part prevented, and may continue

to prevent, as long as he may be capable

of revising it; he therefore begs of thecandid reader to accept of it in its presentstate, and to excuse any inaccuracies ofexpression, or of conclusion, into whichthe intricacy of his subject, the general

imperfection of language, or the frailty hehas in common with other men, may havebetrayed him; and from which he has notthe vanity to believe this treatise to beexempt.

considered as a cause, immediatelyprecedes every effect; and, considered as

an effect, it immediately succeeds everycause

T h e MOTIONS OF MATTER may bedivided into two kinds, primary andsecondary The secondary motions arethose, which are given to or received fromother matter in motion Their laws havebeen successfully investigated byphilosophers in their treatises onmechanic powers These motions aredistinguished by this circumstance, that thevelocity multiplied into the quantity ofmatter of the body acted upon is equal tothe velocity multiplied into the quantity ofmatter of the acting body

The primary motions of matter may be

divided into three classes, those belonging

to gravitation, to chemistry, and to life;and each class has its peculiar laws.Though these three classes include themotions of solid, liquid, and aerialbodies; there is nevertheless a fourthdivision of motions; I mean those of thesupposed ethereal fluids of magnetism,electricity, heat, and light; whoseproperties are not so well investigated as

to be classed with sufficient accuracy

1st The gravitating motions include the

annual and diurnal rotation of the earthand planets, the flux and reflux of theocean, the descent of heavy bodies, andother phænomena of gravitation Theunparalleled sagacity of the greatNEWTON has deduced the laws of this

class of motions from the simple principle

of the general attraction of matter Thesemotions are distinguished by theirtendency to or from the centers of the sun

or planets

2d The chemical class of motions

includes all the various appearances ofchemistry Many of the facts, whichbelong to these branches of science, arenicely ascertained, and elegantly classed;but their laws have not yet beendeveloped from such simple principles asthose above-mentioned; though it isprobable, that they depend on the specificattractions belonging to the particles ofbodies, or to the difference of the quantity

of attraction belonging to the sides andangles of those particles The chemical

motions are distinguished by their beinggenerally attended with an evidentdecomposition or new combination of theactive materials.

3d The third class includes all the

motions of the animal and vegetableworld; as well those of the vessels, whichcirculate their juices, and of the muscles,which perform their locomotion, as those

of the organs of sense, which constitutetheir ideas

This last class of motion is the subject ofthe following pages; which, thoughconscious of their many imperfections, Ihope may give some pleasure to thepatient reader, and contribute something tothe knowledge and to the cure of diseases

SECT II.

EXPLANATIONS AND DEFINITIONS

I Outline of the animal

economy.—II 1 Of the sensorium 2 Of the brain and

nervous medulla 3 A nerve 4

A muscular fibre 5 The

immediate organs of sense 6

The external organs of sense.

7 An idea or sensual motion 8

Perception 9 Sensation 10

Recollection and suggestion.

I.—1 The nervous system has its originfrom the brain, and is distributed to everypart of the body Those nerves, whichserve the senses, principally arise fromthat part of the brain, which is lodged inthe head; and those, which serve thepurposes of muscular motion, principallyarise from that part of the brain, which islodged in the neck and back, and which iserroneously called the spinal marrow Theultimate fibrils of these nerves terminate

in the immediate organs of sense andmuscular fibres, and if a ligature be put onany part of their passage from the head orspine, all motion and perception cease inthe parts beneath the ligature

2 The longitudinal muscular fibrescompose the locomotive muscles, whosecontractions move the bones of the limbsand trunk, to which their extremities areattached The annular or spiral muscularfibres compose the vascular muscles,which constitute the intestinal canal, thearteries, veins, glands, and absorbentvessels.

3 The immediate organs of sense, as theretina of the eye, probably consist ofmoving fibrils, with a power ofcontraction similar to that of the largermuscles above described

4 The cellular membrane consists ofcells, which resemble those of a sponge,communicating with each other, andconnecting together all the other parts of

the body.

5 The arterial system consists of theaortal and the pulmonary artery, which areattended through their whole course withtheir correspondent veins The pulmonaryartery receives the blood from the rightchamber of the heart, and carries it to theminute extensive ramifications of thelungs, where it is exposed to the action ofthe air on a surface equal to that of thewhole external skin, through the thin moistcoats of those vessels, which are spread

on the air-cells, which constitute theminute terminal ramifications of the wind-pipe Here the blood changes its colourfrom a dark red to a bright scarlet It isthen collected by the branches of thepulmonary vein, and conveyed to the left

chamber of the heart.

6 The aorta is another large artery, whichreceives the blood from the left chamber

of the heart, after it has been thus aerated

in the lungs, and conveys it by ascendingand descending branches to every otherpart of the system; the extremities of thisartery terminate either in glands, as thesalivary glands, lacrymal glands, &c or incapillary vessels, which are probably lessinvoluted glands; in these some fluid, assaliva, tears, perspiration, are separatedfrom the blood; and the remainder of theblood is absorbed or drank up bybranches of veins correspondent to thebranches of the artery; which are furnishedwith valves to prevent its return; and isthus carried back, after having again

changed its colour to a dark red, to theright chamber of the heart The circulation

of the blood in the liver differs from thisgeneral system; for the veins which drink

up the refluent blood from those arteries,which are spread on the bowels andmesentery, unite into a trunk in the liver,and form a kind of artery, which isbranched into the whole substance of theliver, and is called the vena portarum; andfrom which the bile is separated by thenumerous hepatic glands, which constitutethat viscus

7 The glands may be divided into threesystems, the convoluted glands, such asthose above described, which separatebile, tears, saliva, &c Secondly, theglands without convolution, as the

capillary vessels, which unite theterminations of the arteries and veins; andseparate both the mucus, which lubricatesthe cellular membrane, and theperspirable matter, which preserves theskin moist and flexible And thirdly, thewhole absorbent system, consisting of thelacteals, which open their mouths into thestomach and intestines, and of thelymphatics, which open their mouths onthe external surface of the body, and on theinternal linings of all the cells of thecellular membrane, and other cavities ofthe body.

These lacteal and lymphatic vessels arefurnished with numerous valves to preventthe return of the fluids, which they absorb,and terminate in glands, called lymphatic