The economy of the animal kingdom, considered anatomically, physically, and philosophically

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hoart to bo the continuat action of the venous blood, but Dotthe alternate motion Or conjunction of the viscus through Whichtho afflux of the venous blood tali es place, according to the severat articles Os Our preceding inductions sit. I90-198, 512,

reason it is that the vibrations of the heart ean be continuod sor so long a time Without the respiration of the lungs, as in thocase of the laetus, of divers, of person8 Sussering ShipWrech, strangled, or any obstructions in the gullet, Windpipe, bronchin,

ns also in aquatic animais. These Vibrations, hoWever, Would not occur is the lungs Were the proximate cause of the reciprocat motion Of the heart.

551. It is Worth our While to en quire for What reason tholungs and the heari are so intimately conjoined, and in What respect specificatly the lungs contribute to the motion of thoheart. We assirin then that the heari, by the assistance Ofthe Iungs, is Lept in the universat motion, Or in the animatorymotion of the bratus, Whicli produces the offeci, that the fibro of the heuri can nowhere bu destitute of iis spirit or lila; this spirit being potired into the Derves at the time of the animationos the bratris. But as this subject deserves to be trealed Separalely, We Shali here Only recapitulate a DK Os iis tending principies. I. The animation of the brains is the universat motion of the whole body, and of ali the nervous fibres Whicli during

in this animatory and generat Or universat motion of the brains, Π. 483, 492). 3. Also the par vagum, Which reduces ali the subaltern motions of the body to this universat motion, n. 493, 494). 4. The lungs are in the fame universat motion, n. 241

84, 280, 283, 367-369,) in so sar as the brutus after birili

relinquisti their association villi tho heari, and conjoin them-selves With the animation Os the lungs. 5. Henee the motion of the heari, whicli is an inferior universat motion, must be Leptin the fame stream Os motion, not as regardS itS OWn propervibrations, but as regards the motion os iis Whole body, and moreespecialty as regards the pericardium, through Whicli the nervos are transmitted; so that the nervolis fibre of the heari novertosos iis vitali ty sor Want os a due supply os spiritS.

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Τhat the whole heari, while it is otherWise employed in reciprocating iis vibrations and motions, is at the samo timo kept in this universat motion n. 287), appears Dom the folloWing considerations. I. The intercostes nerve runs into this organ after is- Suing DOm iis OWn most active ganglia Whicli are in the universalmotion. 2. The eighth pair of nerves of the hered, together With the intercostat, constituto the great cardiac plexus. 3. Thisplexus is placed belween the trachea and norta, in ordor that asSOon as it is moved by the norta, it may also be moved by the trachen, Whicli is continuous With the bronchia. 4. The pericardium is in such continuity With the mediastinum, pleura, diaphragm, and lungs, as to be Lept entirely in the pulmonary motion, and hunce in the universat motion of the brains. Consequently nil the nerves designed to enter the parenchyma of the heari, aSthe intercostat, the par Vagum, the consocialed nerves also Out of the great and smali plexus, as also the phrenio nerve, Whichis in the fame motion, because it is in that of the diaphragm,)pass through the pericardium, and are attachen to ii as their fulcrum Or stay; for DOm their respective attachments We may conclude, that the pericardium has a motion similar to that of the respiration of the lungs, or of the animation of the brain. This is the renson Why the pericardium, When inclosing the Veliis and pulmonary arteries Within a species of capsule, inel Oses also the bronchial branches a long Way up; and also Why it is Leptwith tho heuri in the duplicaturo of the mediastinum, and consequently Within the continuation of the pleura; and why it is attached to the diaphragm. There are moreOver many Other circumstances olearly indicatin g, that When the heari persormsits alternate motions, ali the nerves form stations in the places Where the universat motion prevatis, and finalty in the pericardium ; because the lalter most readily transmits the juice audspirit through the nerves in like manner and at the fame alternate period8. 5. The reason Why the pericardium is uniten to the diaphragm, upon Whicli the more even portion Of the heari's Sursace presses, While the case is different in brutes, is that theanimation Os the human brain is immensely varien and intersered illi by causes proceeding froin the Wili; and consequently by the Same causes the respiration of the lungs is disturbud; as in thecase os every effect Operated by the Will,-in the casu of cssori,

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speech, kc. Amid So great a multiplicity of perturbations, thelieari or iis nervolis fibre Would entirely lose iis vital suid, un-less iis pericardium Were closely attached to the other extremity, or the diaphragm, in Whicli the generat motion of the lungs terminates. 6. In the mean time tho heari itself Will lio withiniis OWn capsule in a state Os perfeci liberty, nor Will it in any mensure adhere With iis ventricles to iis pericardium. Were the case OtherWise, the sursace of the heari, togother With iis vesseis and nerves, Mould be deprived Of iis function, Dor couldit vibrate achronousty With the motions of the Iungs. 552. But the casu is disserent in the foetus, or besore birili, for then the heari can executo iis motions Without the aid of the lungs, because no motion prevatis but the universat motion. Theheari itsolf ulso is kept in the fame motion, for it benis in aecordance With the animatory motion of the bratus n. 282, yc.).

nnimais Whicli pass the winter Without respiration. In ali these instances the motion of the beari again unites itself With that os the brains n. 285 . Without this reunition, When the assistance of the lungs censes, the heart could not possibiy ouilive thelungs. For this reason iis life may be conjoined vitii insensibility and inaction of the muscies, or With privation of the voluntary and particular action Os tho brain. 553. The cerebrum, since it propeia iis biood toti arri the jugular vetiis by iis oron proper forte, and sprinkles inlo it thespirituous suid, and acts moreover et on the muscies of the bo .

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CRUSe, and in the present case DOm One that is superior Or prior. Without the persistetice of the essicient cause, or Without Someniternate excitation, and consequently a restitution eVery mOment of the loss of motion sustatued, no motion Would continue,

but must constantly tend to stop. Heuce the reason for thecontinuatice of the motion of the heari, must be fought for in abigher principie, namely, in the bratus, Whicli uet iapon themuscular sibi es of the heari, arteries and vetus, and tranSmittheir blood by their own proper and living sorce into the Superior cava. Such then being the ossices of the bratias and spinat mar-TON, let HS nexi explain What eauli specificatly contributes to themotion os the heart. 554. With referetice to the cerebrum We may observe, that

veius; nos indoed into the vetiis thenaseives, but hom the sinus of the falx into the laterat sinuses, in Whicli the blood is submittento a mixed action, Damely, the notion both of the cerebrum audos the cerebellum, by Whicli the bl od is forWarded tuto thebesore-mentioned Veins. The cerebrum moreover derives ali theblood Whicli floWs in iis different penetralia, as iis ventricles kc., into the fourth sinus, Where likeWise the blood is received by a miXed action, namely, the notion of the cerebrum together

With that of tho cerebellum, by Which also it is propelleti stillfurther. AlenuWhile this action is the cause of the motion of the heuri considerest as arising fro in the blood, because the bloodis transmitted by the forco proper to the bratus through the jugular vetus into the vena cava, since it is the part of thebrains to act upon their OWn proper blood. This derivation ostho blood Dom the bratus toWard the heari, may be called a livinglautitain, sor as Osten as it talios place, it excites the circulation, Without whicli action the circulation after a seW turtis Would SpontaneouSty cense, beenu se it has a continuat tendency to Stop. It may indeed in some mensure bo compared With a Wheel, Whichrister being once set in motion, is made to continue moving by a Series of perpetuat impulseS. 555. It is Worthy of remarii, that the cerebrum, With theuid of the cerebellum, determines iis OWn proper blood moreos pecialty to Ward the right auricie, Where lies the proximate cause of the motion Of the heari: it determinus it, sor iustance,

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initer soWs into the subulavian at a someWhat greater distanee Dom the orifice of the auricle . For the great Or falcisorin longitudinal sinus, Which belongs to the cerebrum Only, inflecisitself for the most pari toWard the right laterat sinus, and carries thithor the litile canal grooved o ut On tho occipital bone. Out of Durteen subjecis,' says Morgagni, Whicli I examinedSUCeeSSively, there Were Only 1 ur in Whicli the laterat sinuses Were a bifurcuted continuation os the superior longitudinat Sinus . . . . I Observed that the sinus into Whicli the wholo longitudinal sinus is produced, is most frequently the righ for out of the remaining ten subjecis there Was only one in Whicli it Was produced into the lest. I horo re in the lest mali of thoright sinus, as deflecting Dom the longitudinal sinus, the orifice

this phenomenon is to bo found sol ely in the place Where theblood of the sinu ses is finalty diseharged, since it is hunc e that

the stream and connection Os causes is continuatly floWing. Forin the be re-mentioned Case, according to Eustachius aud severat Other anatomisis, the right jugular vein, Whicli is a continuation of the right laterat sinus, and lience of the longitudinal Sin IIS, approaches nearer than the lost to the divarication of tho subclavinii veitis, and pours iis biood therelare more immediately into the vena cava und right auricle. Helice as the auricleis constantly requiring a Desii supply of blood, the nearest channeis must pOur in their OWΠ blood, and conSequently, asbeing the nearer, the right jugular vein must pour in iis bio dbesore the lest; and lieneo the right latores sinus; aud in the

the former, the longitudinal sinus. This ordor os fluxionis srst doterminod in embryos, When the litile canals of the fluids formed, and when the longitudinal sinus maintains the very closest connection With the heari, or When the heari is dependent iapon the sinus, so sar as it is dependent iapon the synchronous motion Os the brain. Henoe it is that tho right trutili of the par vagum, Which by iis emissary branches supplies the right auricle, and which also passes betWeen the carotid artery and jugular Vein, unites this velit so very closely to itself

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Under the appearanee os a cellular, silamentary, and as it Were membranous Sheath. Henue also it is, that the lest recurrentnerVe, ariSing Dom the par vagum, insects itself toWard thelarynX, and iis musoles and rings, more suddenly thau theright n. 36 I). Moreover, the inferior Or anterior Sursnee Ofthe cerebellum is divided, as We knoW, into certain protube-TRI COS Or provinees, discriminuten Dom euch Other by riliges. ΝοW the larger of these protuberances, Whicli lies under theSetranSVOrSO Vermicular processes On each side, is formed into a Variety of solds, Whicli run in a parallel und transverse direction, and penetrate far into the compages of the cerebellum, in Sucha manner that the latior is insinuatod doWnward more deeplyon the right than on the lest fide. Honee the right portion Osthe tranSVerse septum, or of the second process Os the dura mater, When Strongly agitated, desecis With iis orifice und canaltho blood which is flowing through it over the sinus, rather inthis direction, or to the right, than in the other, Or to the lest. In the meanti me, test the equilibrium os the blood should bd do-stroyed, the laurili sinus, With ali iis biood Dom tho interior of

the cerebrum, is draWn more especialty toWard the laterat sinus and jugular vein of the lest fide; henee there arises an equationos the wave; for Which purpose also another ShOrt Sinus is Some- times extended bet Neen the two lateres sinuses. In like manner

there is a branch sent doWn obliquety froin the right jugularuein to the lest, Ubere the lalter inosculates With the subclavian;

not to mention Other communications for producing an equationos the blood, or supplying the desciency of one part by the

excess of another. In this manner there is an equation obtained not only of the quantity, but of the quality of the bl ood;

for the blood Whicli passes hom the choroid plexuses throughthe laurili sinus, and for tho most part dis harges iiself into thelest laterat sinus, and consequently into the lest jugular Vein, do es not seem to be so deprived os life as that whicli retiarns Om the cortical substances of the brain, and Which having asit Were tost iis vitality, rutis into the longitudinal sinus. In themeanti me, We may Observe, that ait these circumstances are buttiniis in One and the fame chain os causes, as is likewise thelaci, that in man the agygos floWs into the right cava; that theright Iung, together With the right portion of the diaphragm,

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excoeds tho lest in bulli and extent, Whicli is Only the continu-ous effect of One and the Same cause, particularly as the lungs animate synchronousty Vith the brains n. 280, 283). Thus uroseo hoW the brain contributes to the motion Os the heari, or tothe motion of the right auricie, Whicli is the Wheel of the cardiae motion; me seu it also in the faci, that tho brain di- recis iis biood for the most pari toWard this auricle.

556. It is likewiso Worthy of observation, that the brainpours into the blood soWing out by the jugular Velias, a copio IS Supply of Spirit or spirituous fluid, Whicli animates and vivifies the whole blood, and hetice iis Whole circulation ; for the blood may be so sar callest suid as it is partaker of this spirit, since iis fluidity is not oming to mater or serum, but to this animal fluid, Without whicli it Would bo nitogether fluggisti, liseless, and in- cap te os acting and circulating. This is sufficiently evident

labor under a deficiency of this fluid, or Dom indisposition byreason Os iis irregular commixtion or motion. In Order there-

soro that tho blood may be straightWay made as suid as possibie, and that this may be essected in the heari, Where the ingredients of tho blood are first confused and commingled; that isto say, in ordor in this firsi and last stage of the circulation to prevent the blood Dom groWing crude, and coalescing into irregular pieces, or into grumoVS, fibrous, indolent, viscid, and gelatinous substances, the brain immediately transmits a quantityos spirit toWard the right auricle or entrance into the heari, for nil the constituents of the blood Where the proximate cause of tho motion of the heari and the circulation thetice depend-ing exisis; also at the fame time toWard that part of the sub clavian vein Where the neW chyle issues Dona the thoracio duci.

It is With a vieW to the performance of these hight y necessaryfunctions, that the whole cerebrat laboratory for preparing and deriving this suid, is provided. See n. 360, 36I, and the Ρaris whieli mill follow on these subjeQtS. 557. Τo the preceding causes We may add another arisingsrom the brain, namely, iis acting upon the muscies of the body, and by means of this action propelling the bl od tuto the two venae cavae. As this action is performed by means os a previolas exercise of the Wili, there is thus in the brain as it Were a living

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solanta in os motion, Whicli continuus the circulation by an actualinpoliring of the blood. But stili this is a very remote cauSe; for OVen When the muscies ure ni rest, as in fleep, the blood is nevertheless transfused Doui the Whole of the muscular regioninto the vena cava. In the Pari on the Musules We design to She , that When the muscle is relaxed, the bl od flows throughthe communicatory vesseis Whicli me have called commissaries

n. 408-417), and that When it is constricted the case is other-Wise. In the meantime it is a subject most Worthy of enquiry, What is tho state of the body, and What the state of the brain, during Sleep, and Wal eminess, and hoW the circulation of theblood is at these periods promoted in the brain and the body;

scarcoly distinguisti the one from the other; as in the respiration of the Iungs, in performing whicli the arch of the thoraxis Opened during Wakefulness in a manner altogether different, and villi different nerves and muscies Dom those Whicli mesiud employed during fleep. The same Observation holds Withregard to Other organs, so that it is at this period that causesare occupied in repatring ali the losses Which had occurredin causates during the day n. 216, 217). But as this subjectis os vast extent, and the enquiry into it supposes an investigation into the whole corporeat System; for One Viscus SieepSand wakes disserently Dorn unother; and as in different viscera the States of WAefulness aud fleep alternate in disperent manners, for the cerebellum and iis nerves are more Wahesul during the fleep of the cerebrum and iis nerves than at Other

tirely froin the influx of the red blood into the vesseis of the purer Or White blood in the brain, the consequence of Whicli, is, that ali distinction os degrees immediately peristi es; for the

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nervolis or medullary sibre together With iis suid, cannot floWinto a vesset of the red blood except through tho modium os avesset of the puror blood. When this happens in the brain, it necessarily follows that not one os iis cortices tori is capable os a particular Or individual elevation, nor can any one of the Senses be, Since a perfectly distinet subordination os degrees is required sor their exercise; and when this distinction or discrimination is intercepted, the cerebrum can no longer apply iis poWers, but is bound to animate in common With the ever-Wahelat cerebellum. Henco in those subjecis in Whicli a lessdistinction os degrees prevatis, as in idiots, in perSOΠS Sleeping, and the like, the will and sensation are alWays obtuse and dullin proportion. These observations hoWever are Only by the Way, and are made merely With the vieW to enable iis to deduce DomkDOWn causes hoW each brain flows into the body at this time,

and hoW the channeis are opened into the vena cava, in Orderthat the circulation may be continued. These, With a varietyos other subjecis, can never be traeest up to their CauSes, Oropened to viem Without a distinet notion of the subordinationand coordination Os degreOS. 558. The cerebellam is a remote e scient cause, since it rosis

Duntain, inlo the superior vena cava; and Alis and animales thecardiac nerves, and the nerves of the arteries and veins, with spirituous suid. The cerebrum is a more remote cause thun thecerebellum, for the cerebellum more Especialty seuds doWn theblood of the sinuses into the jugular vetus, and ut the Same timetransmits the nerves arising Dom iis medulla, namely, the inter-coStal and par vagum, to the heart. Willi rogard to the sirst Statoment, that the cerebellum seuds doWn tho blood of tho sinuses of the head into the jugular vetus, I observe, that thelaterat sinuses, Which receive the blood of the Other Sinuses, asthe fourth and the longitudinal, are entirely under the rule of the cerebellum; they are carri est doWn like an incurva ted retortupon the petrous portions of the temporal bones, and attachthemsolves to the arm of the transverse Septum Or Seconii prOcess of the dura mater, Whicli passes in a curVe correSpondinggith the convexity of the cerebellum. Thus under the rule of the cerebellum, they are destitute of membranouS eXpanSionS,

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cordS, SineW8, solds, Windings, and miliary corpuscules, and areinvested with a coat os reticulaten fibres; so that When the cere . bellum, by iis alternate animation, moves about and preSSeS

and are again restored on the escapo of the blood. And thelaurili sinus iiself, Whicli at otio fimo Wo find ut the head of the Sinus of the falx, ut another in One or other Os itS RrmS, genOralty in the lest at otio time belWeen both, ut another opening Sometimes With a single, sometimus With a double mouth-is recumbent upon the cerebellum, With Whicli, along the greater part of iis circumferetice, this sinus is in contact. But thecerebrum tolaches it only slightly in the commissure of the processes. The cerebellum Hso in re certain mensure gOVerus thesinus of the falx, for the sinus depends upon the falx, the salxupon the transverse Septum, and the transverse septum principally upon the cerebellum. Τhus We see that it devolves principally upon the cerebellum to forWard the venous blood hom the interiors of the head to the jugular vetus, and also in Somemeasuro the blood of the ventricies of the cerebrum, of their choroid plexuses, and of the chemicat laboratory both of tho cerebrum and iis organs. We see also that the cerebellum feems to be appotia ted to the ossice of the generat administrationof the functions in the animal economy, While the cerebrum is employed in Walching over the a1rairs proper to itS o vn system), and more floWly and silently performs iis animatory functions; of Hl Whicli subjecis Wo shali spea in special Ρarts of Our WOrk. The cerebellum therefore, as far as regards the transmission os the blood through the jugular vetus into the superior cava, is a cause of the pulsation of the heari, but a remote cause; for the bl ood is expressed by the proper and living force of the brains, through the medium Os as many QOreula as thereare Simple Spherules of the cortical substance; the bratiis belligilte movers of their oWn blood n. 219 . 559. ΜOreover the cerebellum furnishes the heuri itself, thatis to say, iis ventricles and auricles, the large arteries and VeinS, and for the most part also the minutest arteries and Veina of the body, Willi nerves sent out Dom iis medulla, namely, the intercostat and par vagum, Whicli are the Ompring of the cere- bellum n. 485, 490). Hence also the cerebellum provides the