; iiiii ::;r::.::";,:|||:|;r;i:i?;::r;;.. iiiL-Ssii!:'!?®^^ iflS!:-*.?1" feaKKsr riirr.-:;..' ■ .'■:. :.-u.-:"?J| :«its..,v-.-!:j. ■-:,:.;!:HiiHii&i:::!i::;;:!-:;'; . SiT?^: . ,1"' ■',':1 ^Siliiiilililfeffi NATIONAL LIBRARY OF MEDICINE Washington Founded 1836 U. S. Department of Health, Education, and Welfare Public Health Service f •' ■ 'ST&TEMEHT OP A THEORY OF LIFE. FoL'T.nrr) e-N OBSERVATION'S 6$ EXPERIMENTS BY DAV2D PORTER, BZ. P, -.\\«'W^ w* Put*-ciii* by W. Jacavxas, £ro\v&svih,e, ?>:..C 10£jT *a TO iH2 HSA'DER. T"5! vft§uenr?33 and uncertainty of prevailing opinions en tbe'sub- V^t. oflife, must bdecd be humiliating to every admirer of pb;.;i,.;..! cccc.co, but particularly mortifying to the practising physician. In* fiMiitcd with the lives of his fellow creatures, I.e h or'in after. o.v? ;!■?<; hi-r.self of all accessible means of i.ifor^atsoiij in most painful unco*. tainiy, as to die course he'should pursue, while every good feeling o his nature is calling o<> him to render service,..and avoir! injurious or even fatal mistakes. Sensible of this tremendous responsibility,. an opinion, so far simplified, that I feel no apology ru.ssarjAir, suW.it ting ~:y inquiries to the facidty. An enlarged discussion of d e sub- ject, accompanied »vi'h details of such experiments and observation? cb I have m;,de, will probably appear before long. The present is a mer3 sketch of opinions I have bee* led to adopt, and is principally desiprJ ed for the consideration of a few scientific friends and others towhoT* a Si rmtj 'vih a hope that the doctrines '.\?-\y be nxne raph-Uy m;»Ur v> ■--fey aid from rbeir communicaiious, which are hereby respectfully'&■ '■■. Iicited. The statement I a«j aware will suffer at present by being" Vvt accompanied with detailed proof, yet I feel confident that-to the philo- sophical reader, much proof wilJsuggest itself as he proceeds, & wiv.-b . jpore may be'had, by the performance of a few simple experiment?, which will naturally suggest themselves. The cctfgrui-fy, too, and nra- . rtuix} support of the parts of this theoiy, together with its simplicity qDastitete an amount of proof in ka favor,which, wo> hope, will arrrc! fcitcridG^notwuhsianJ';^ The application of the principlesad'/anced, is extensive as Naturar herself; but it is intended here,! a state o»ly, as briefly but ccmprchcn s'rvely as-possible, the leading doetriuos as they relate to the science ct ^Medicine. In,order to this, howeverj env views of maifeT in genen?, .jpust"first be stated. -Boccndly, will be" noticed, life and living matter; "Ibwdry, »heparts of the human body, principally concerned in the deve- lDpement«fljfejpjurthJy,thefunctionsofthe human: body; fifthly, tha ^nctionaofmernindr sixthly, di^eaaesofthe body^seventhly,diseases of &e mir>3i& lastly,remedies. The easy & satisfactory explanations of lite tatter subjects, & pariieular!yof diseases &, their readies which are .finished by the principles here advanced, have been a source of much delight to ayseif. How they will meet the v;ew# of the facul- ty in general, time must reveal. Such as, after a candid examin- ■•Mion, believe that3 new field of investigation is- ©pened, are cordially •♦^frted to assist in exploring it, by -THE AtJTTIGH. 3n"S*.VKSvitLn;' Fayette County,- Pa> I t*\ f I. OF 'K.iTIXR IN GLTlJiHA^. f . Prixa>-y Principle?.—Matter is naturally divided into, iwo f»r>. mry principles, which shall be oumed simply solid and fluid. Solid,, i$ composed of indivisible parts or p^rticles,,of different forms, whici. produce the differences of elementary..bodies. Fluid does not cohere to form.ultimate particles, but is essentially repulsive of itself and infi- nitely attenuated. Natural bodies consist of solid &._ fluid, in varying proportions; y,ot their solidity and fluidity are not owing merely to the proportions of solid and fluid they contain, bat are mixed effects of these proportions and the structures.of their component particles, Toe.terms solids and fluid, must here be understood to denote these- primary principles and not natural bodies, unlessjhe latter are named.. 2. Primary La\m.—Sn»lid particles.lend to occupy the least pos- sible space, or in other words, to perfect solidity.. Flu id, oruhe olhefj hand, tends to.occupy the greatest possible space, or in other word^ to equal and universal diffusion v. 3. Diffusion.of tfte Primary Principles.—?As fluid tends-to equal/ diffusion throughout space, s.olid particles with regard to it are vacua*, which it enters-and fills in .varying, proportions, according to their va- rying cipi':iti;i3 .md susceptibilities, arising from, their- differences.of, form. The.p:irticles thus enlarged, with the.exception- which will be er.sntioned hereafter, are kept in,contact, so as to .avoid interstices or pacua of solid. Artificial vacya are only void;of solid, for they con* lain their.full quan-tity of fluid; whicheannot be excluded in the leas! from even the torricellian vacuum. 4. Composition of Bodies.—Bodies are composed of solid parti- cles, charge J with fluid in different proportions. The amount of fluid o,solid particle can receive, is the measure of its capacity; and- this ie different, not only in different elementary particles, but m, the same, under different degrees ofpressure. As all part icl-s exclude fluid af? inuch as possible, manvcoutain less than u,cir capacity would admit- Of. Tlie facility with which fluid-enters bodies,is inversely as their ex-- eluding powcr,.ar.d may be called their^ susceptibility. The relative qctaniities which bodies contain in equilibrio, are their specific quan- tities. Any addition to, or subtraction.fro#i, specific quantity, consti- tutes the plus or minus state respectively. 6. Attraction or Gravity.—AH particles of bodies arc recur1 i|l|\Vpif>-. Wfl<'»!'<> H^thf-V .TllilllS Wlf m particles containing less essential fluid are within reich, the redundant fluid of the plus particles, having no other outlet, is forced on those in contact, and by these on the next, till an equilibrium is produced. This is healing and copling and proceeds more or less rapidly accor- ding to the capacity and receptiveness of the successive particles, which, together, determine their characters as conductors of heat or calorick. Bodies ih the minus state, are exactly opposite to those in the plus, as regards the above explanations. They attract plus particles, as- sume a nitrogenous atmosphere, or acquire equilibrium by receiving fluid from the adjoining particles. 8. Ckemical Union of Particles. Simple particles are disposed to unite into compounds, as they are opposite in their proportions of es- sential fluid, and these componds may again unite with other simpie or compound particles for the same reason. Thus where two particles containing different quantities of essential fluid ate in contact, that which contains least, in thateffort to part with its disposable fluid, which is constant with all particles at all times, is contracted & crow- ded into the capacity of the other, occupied by its disposable & tran - sient fluids, which latter are crowded out, and the disposable fijid thus thrown off is the heat evolved in composition. In forming compound particles, it is nece^sry—1 si. That the enter- ing particle have so little e.-^entiai fluid, tnat it may contract *,.i(j'i- cityitly to en'er the capacity of the receiving partic«e.—- Oxygen & a- cids, which are chiefly co nj»oseu of it, are best, suited to this purpose If is nece-mry, also, that the receiving particle have enough essentia! fi.iid to invite the union. All combustibles are of this kind; but phi- tiri'i. gold, s-il-.-p.-, &,:•.. for want of it, do not unite with oxvgen. It is, in (he last place, necessary that the receiving patikle have sufficient disposable and transient fluids, to leave room in their escapp, toe the entering pa.r'icle. For want of this, oxygen cannot unite with many substuices which possess the most essential ihiid, until their disposable or transient fluid is increased, or, in other vords, fill their temperature is raised. They will then receive oxygen till their caps-- coy is filled, when they are vitrified. Some bodies, as potasium, sed:- urn, phosphorus, &,c. contain disposable fluid enough, at (hecommcu temperature, for combination with oxygen. The capacity of the cou> pound, is always less than those of its constituents. 9. Temperature of Compounds.—As simple poitides in uniting part with their fluid, so compound particle? in receiving fluid are sep- arated into their constituents. This separation like the union is grad- ual, and proceeds as the fluid increases from that quantity which rr proper-to the compound particles, to that which constitutes the sum of their separate amounts. Fluctuation between their extremes pro- duces temperature. Thus hydrogen and nitrogen igasses, being chief* ly filled with essential fluid, cannot separately vary their tempera!;ir«i or stock of fluid to any great extent, or their vchune under the same r''e.saere. But combined With «?vB«n ^ ;~,..».-----;—~ »«=.v»vovicij t *■! water, they produce these aflfect3 by. flucitiating- between cornj^t^. union and complete.sepniation.. 10. 'Light.— When during.corn position flgid-is^xpellerf-more ra- pidly than it can be received by the contiguous particles, it is thrown »,ff and passes through all repletembodies as air, . -■ ,-c.tions of which prevent an :o>njea!'.--i'e return officio when- the. ratise of displacement is removed. Bodies in ihis state are said to, bo ,osriled or charged, and aft: ^t or repel-each other..r.s their opposite or similar parts are presented. Sume ant-stances, & especroiiy ferrugi*.. nous matters, are capable of adapting, their particles so as to remain permanently in this state, and are then called magnets. Their opposite extremities or poles will then permanently attract or repel others as above. The Earth itself* beeing, permanently plus to the North an;* minus to\the south, is a. great magnet, which regulates, all minor ones. 12. Galvanism.—The capacity for essential fluid which a particle! possesses, admitting neither increase nor decrease of amount under n given pressure, can only increase in one part by decreasing in the op- posite at the same time. Bodies may thus become charged by a plus and minus state of /their particles, but cannot give passage to fluio', and are consequently electrics or nonconductors. The capacity for disposable fluid, by admiting its passage through the particles, constitutes non-electric or conductihg power; of .course^ the more of this capacity a body possesses, the better conductor it ir When a conducting body is, charged, there is not ? charge of its par- ticles, but an accumulation of disposable fluid in one side, and a pro- portionate deficiency in the other, of the body. If all fiuidal press^ie. tfereremoved from part of the surface of a body, then it is plain, 'the disposable fluid of that body would be thrown from, that part, with a. power,as its quantity multiplied by the fluidal pressure of that body; consequently if two bodies are placed in contact, the disposable fluid- of the one will enter, the athqr with a power, whjch is the difference of. -^^.^--•r-^-^^vr^uijMPp.^^jra.v fi entering thp latter b<*i.y4 thft (tfj fhidfv*.letter charge its particles or pass thro* them to chargeihz t-ody, as they are electrics, or conductors, 'orin other*words, as thtaF ' \japacity for essential or disposable rluid 'is predominant. Suppose, a coaducting b&dy, asa plate of silver with a 3\ridal pressure of 10 an J disposable fluid of 3, giving an expelling power of 50, suspended )a 'ihe air, its" 5, surrounded on all sides by 10, will remain guarded as.ifc were in its centre. But suppose a plate of zink, with a pressure of 1 sa.d a disposable'fkwd of G, giving it an expelling power of 42, brought into contact with" it. The two then form ono mass, guarded on its opposite sides, by powers of 50 and 42 respectively. This will forcci -'Slid from the exleribur surface of the silver to that of the zink with a if-ower of 9, and will at once create a minus or nitrogenous at- mosphere of 3 for the silver, and a plus or oxygenous one of the sarao 'degree for the zink. If We now separate' them, they will remain posi- tive and negative For a short time by means of their opposite atmos- pheres. Leave them together & connect their opposite titles by another conductor, arid we will have a continual circulation of fluid from the •silver to the zink, and buck agairflhrb' the conductor to the silver. If fh'tscOmrnunicatiOn between the opposite surfaces is not formed, the axternal zink surface, by uniting with oxygen, will be enabled to throw off fluid, while the opposite of silver will receive an equal quintity from the nitrogen on its surface, and thus' a slow passage of fluid will be maintained. If we place two other similar plates in such position, that the silver surface of the latter may receive the fluid' dismissed during oxygenation by the zink, of the former, and then connect their opposite surfaces, the effect will be doubled. In this way, by increas- ing the plates and intervening oxygen, the effect may be increased in- definitely, as is exemplified in Voltaic piles. Suppose again fhe'jiuman hand applied to glass tube, the former be-, •r»g a conductor with a greater expelling power, the latter decidedly electrical with a lesser expelling power: Now fluid will pass front the hand to the glass, and entering the capacity of the first range of . Uredus particles, fluid is thrown from their opposite sides on the next, and so on, the opposite side ' of the farthest range will be minus, hav- ing a nitrjgenous atmosphere. Thi3 effect, however, will be slight, as the oxygenous atmosphere cannot find access till the hano*' is re- moved; but by reapplying the hand in quick succession, as-by friction fluid is gradually accumulated and secured by successive additions of oxygenous atmosphere, till the particles are fully the tube excited. The charging di the Leyden the samew^y. 3 u, of'riPE and ifviNb atATfca. 13. Organoid particles.—A certairi number of different element te'-y parficterso attangcuV^to contain betv^en them aa inteiestice and minus, or explained in .f6) *.-r keaeivmg a potion of their complement of ibid is an rngsiozej ^article dr globule, and the interstitial fluids of such globules procliu 'he various phenomma of life arid vital heat. As the organized par- ■He- parts with interstitial fh:id. its components arsume their respect ivo ■U tractions producing successively feiruntaticri and putrefaction. 14, Their primary law.—The globules like the ul' imaie parlich 3 * nd to Occupy the least possiid' space, and consequently toexpel their fluid. The interstitial fluid is received and given out however, more slowly- than that of the ultimate particles, and hence the globule c;.n- r.-ot. receive any addition to its interstitial fluid,' except from that of other globules;' because the fluid of other ultimate particles, instead of waiting a inception by its interstice, is more promptly received by its TTKnpoVmts; and hence too, fluid pas-es frnrn globules to ultimate tar* ;icles more slowly, altho' the latter may be negative. 13. Their Variations. The particles of lymph are disposed to 'issurne different distances from each other as their quantity of inters- titial fluid is varied, from which it follovo, that in contracting they become positive and part with it. Thus, when blood is drawn we •nay observe fibrin as it parts with its fluid disengaging itself from the larum, and gradually contracting its dimensions. .The same would take place in the contraction of muscular fibres, could they in the same •nanner disengage themselves from the vessel?, fluids, nerves, cellular substance, &c. which constitute so large a part of the volume of flus- hes, and which, not admitting of compression, increases their thickness * in contraction nearly as much as they diminish in length. External pres- sure increases the power of the globules to expel their fluid, while ex- tension renders them negative, and disposes them to receive more. 16. Division bf interstitial fluid. * Interstitial fluid, like that of ihe ultimate particles, may bedivided into essential, disposable, and 'ransient, which produce respectively similarphenoinina.' The essen- ria! fluid, according to its proportion, produces'non-conducting.or e- jectrical power, and the globules do not part with it bbt as they are disorganized. This is seen in albumen, fat, cellular'substance", &c. The disposable fluid produces conducting or nonelectric power, as ap- pears in medullary matter and coagulating lyrriph, whether fluid or thf muscular tissue &. lymphatick glands, by 25. Stimulation. Any thing which causes the disorganization of a red particle, in a leceiviag nerve, so as to set loose its interstitial l.ii.I, is a stimulus, and the fluid thus liberated, is vital heat. 71ie exorcise of this power is sinnuLtion which depends for cc« .-t ;:=,?:- «ce On the distraction of successive red particles, and* the renewed supply of successive portions of fluid in the nervous system, to counterpoise tt. Tims suppose any part of a receiving nerve pressed till a red par* fide is* disorganized, and its fluid driven off; the carbonaceous residue of this particle will be negativeand attract fluid thro1 the medullary friibsUnce in quantity sufficient to form an equipoise. Stimuli miy be divided into mechanical, cheuucal, and mental.-y Mechanical stimulants product; their effects by pressing or extend;'ng fha nerve, so as to destroy the red particles it contains. Chemical stimulants so alter the relative positions of the nervous particles that the red particles are necessarily destroyed in passing them. Stim- ulation in the latter case continues for a longer or shorter time, after the stimulant is removed. & even after the destruction of.the red particles ceases, it is often a considerable time before the nervous particles so fir Assume their former position as to yield to a renewal of the same impression. This restoration in some cases does not tike place for jreirs or even during life, a3 is the case after stimulus of infection from smdlpox, scarlet fever, measles &c. Mental stimulus is the stimulus of the mind on the brain in the production of thought. It is physiologically similar, and perfectly reciprocal with other stimuli.--*> The effect of stimulus on one of the receivers of a ganglion in fur- nishing fluid iupy be increased without any decrease in that of the others, until the full quantity which the ganglion will transmit is brought forward. After that, any increase of effect in one, produces a corresponding decrease in that of the remainder; the stronger stim- ulus still suspending the action of the weaker in due ratio, as it fur, nishes fluid. On this fact is founded the principle of comvttr action oj eounterirrilation, so important in the practice of physick. The power of stimuli increases as the fulness of the cellular vessels of the part, and their fulness in turn is increased as calorick' is libera* led to expand them. 26. Respiration. Muscular matter in elongating becomes nega- tive and at'racts fluid, by which means the latter is brought thro' the discharging nerves from the whole receiving system. The trapcziu.s Vi'! constrictor muscles of the pharynx, by means of the spinal ac* ccssory nerve, are thus supplied with the means of elongation without checking on the general stock. This nerve mostly arising from the posterior fasciculi of those nerves which supply the superior extre- mity, produces a reciprocal {connection between the muscles of th« arms and those of deglutition iti eating. But tha rou^cutar inaUt*: constituting fhs ultimate muscular ctffi$ F.H-? . vi the kings, ny rnea»«? of the par vagum, is tnc principal1 instrumo' for attracting fluid from the whole receiving system. During in spiration blood rushes into these cells, from the pulmonary nrteriei', which terminate in them, while air fills their celluhr envelopes in which the ramifications, of the bronchia terminate- The entrance of blood renders the muscular cells negative, by which means, fluid is at- tracted to supply them. During expiration the carbonised air is driv- en out and the fluid which is again forced from the muscular cells, &- prevented from regurgitating by the valvular structure of the brain at. once renders all branches of tho nerve positive, and furnishes to the lymph of the blood as it passes the longs the fluid necessary to meet iisgieat expenditure in digestion and absorption. These effects arise from each inspiration and expiration, by which the lungs are at Once an outlet for carbon and a grand pump for drawing in «nd dis- charging the fliid of the body^ In the fetus this latter office is per- formed by the thymus gland. The positive state of the dischargers during expiration pioducfp *he following important effects. Those terminating on the inner sur i ice of the heart, besides absorbing as we shaIk-see, the carbonaceous residue of stimu) ition from the whole system, commonkhio to it a. portion of flu id preparatory to its oxygenation and elimination from tue lungs. Those terminating in theorganick fibres of the stem ici- furnish the means of free dilatation for the reception of food and dn.c, and prevent tneir immediate expulsion by vomiting when tho receivers- are excited. Those terminating in the ultimate muscular cells of the liver dilate them for the reception of portal blood, which could not otherwise gam admission, without aid from the heart. Wh mencement of which process in a negative state of its subject, ffl inaik1- od by a bitter taste, as h most evident in cystic bile. 27 M x ular motion. When receiving nerves which terminate i*i .nuscular ri>,res are s;iniui ited, fluid escapes from the fibres and nislu..'- ?<-■ the negative resi.'..if ofthe reduirticies, producing con'rac'.h.-,-. - [ >2] When d'slending force is applied, the fibres becoming negative a*r,;rt a-ttract fluid from whatever lymph is in contact with the medullary m Uter of their nervous fibrils, and are thus elongated. These nifects are muscular motion. When contraction is produced by the operation of the will on the functional nerves of the brain it is voluntary motion Ira receiving nerve terminates in muscular fibre by the inteivention ut cellular substances and a discharging nerve terminates directly in tho* same, then as the former is stimulated, fluid rushes fr©m the latter, but is arrested in the fibre, which is consequently elongated. Thus tire tdosso-pharyngeal nerve by means of a spring of par vaguni, wdiich accompanies it, iris the power of elongating the linguales and other muscles of the tongue. It also sends a brunch with others from th<: par vagurn and spinal accessory, to the constrictors of the pharynx for fhe same purpose. 20. Absorption As regards the substance taken up, absorption ~'i< positive or negative. The receiving nerves creep'ng along the ran? f liar absorbents., terminate on the inner surface of the glands and ah Sori through the cellular lymphaticks, all positive substances which may be thrown into tli.-neurile.ma by the cellular arteries. The fi- bfm, albumen and red particles which escr.pe distruction ai>e thus at i/acted to the lymphatick glands, whence they are driven into the Lfrea: v-'insby tjicmu^ciita^ lymphaticks. Chyle is attracted lotheme infer cJ, ghndi and driven forward precisely in the same way. Fibrin in all -en- ■ses Iosps a partof its fluid as it passes lymphatick glands. On the oth- er baud the discharging nerves which terminate on the inner surface ;jf the heart, being rendered positive during expiration, attract all negative and orcyger.ous substances within roach. The residue of the ■Ted particles, is thus-attracted thro' the cellular veins, to the heart: for although fluid rashes to it from the muscular fibre and lymphatick glands, it can enter but very slowly,.because Ihe interstices being ob- literated or in other words the globules disorganized, there is no room *;i't but in the ultimate-particles. Before the entry then is»made, the negative- art iter is sn itched away as it were, by the dischargers of the heart during expiration. W iter vv'-th ait other negative or oxygonou:- substances are also attrac'ol in thesam? \v:y. If such substances are veo extern-il to the n<. orilem.-, they are brought in through the pores, by this same power, and then,re by the cellular veins as before. 'in this \\\iv water &c. are Liken up from the bowels., and passing thro' < 1 to portal veins, must traverse the liver. f:3. Circui.Uion of idoo-L The heart and muscular blood vessels - ore reciprocal stimulants, and in good l.Oidih, the power of the former, is exactly eqml to the agnregaie mruer of the latter. When the heart .. oirr.icts, tne muscular ves-^-is are dd ited until their nerves are stim- •oated'aiid they in turn contract and fill the heart. When, the heart .-• dilated to a certain point its nerves ;-;r agaiuslunulated,it contracts ■■);■■! again fills the vessel? and thus the circulation is maintained. *.». 2) >..*<:■>■ i :>/>.. Wh< -., food '■, taken In,- '.!>•. tour, it I' is o:-. cited &. [ ^ ■ 'yv,e-.:.,e,'^ cfifisbndly -;■'> ;rs to keep in clooe coitact with ri.-. -senler..;; To facilitate this, its diverticulum the spleen, is enlarged and gives passage to more blood which, with a greater quantity also forced into the neoi'ick artery, increases the functions of the liver and produces more bile to meet the food in the duodenum. As the food comes in contact, throu'jh millions of pores, with the blood of the cellular'ar terie.'ji's lidolnilfs are aradtmilv charged from the lymph until tnev ere softened into chyme, and finally melted into fluid matter, sufficiently positive for forming chyle and undergoing absorption, l'hjs may also take place with organised particles placed underthesnme circuin* s'lio'cr- in any part of the body as is well known of animal ligature.--, c'-rr. A portion of food remaining in theslomaeh and becoming highly ch'irgcd, iorms the gastric final. As soon as the chvme leaves the stomach, it receives the bile which by its a!'-, dine properties, prevents aaccsf-ency and by its bitter qualily forms (he most appropriate chemical stimolus for the bevels. In those aitim -la the fnod of which contains but little Of the bitter principle tl-ft the bitter qualiiy of the biieis more eilli;Luaily secured by a gait bladder. As a groat supply of fluid from cord recti 0^5 and absorption during digestion must gradually cense as tlie process is completed, senm provision is necessary to guard against the consequences of a reduced supply \a the great semilunar ganglion. This provision is found in rliep reerr.7,?. Having no blood-vessel particularly appropriated to if, like other glands, it receives branches from those of the contiguous organs, by which meinsns those organs become empty 01 contracted »V5 arteries receive a buger supply of blood. TIrs keeps up the supply rf Vmid by an increased exercise of i's vascular fibres, as well as by the nh«?orp'ion of lymph which is thrown off .11 secret i'en, by its ceiluaa- erieiies. 31 . Sccrc'ion,n'drili'}n, and growth. Of tlie blood which ispottr- r ! into the nerves from the cellular arteries, whatever is not.taken up by venous and lvmphatiuk absorption, either passes off by the pores 0.1 •* fvcretories, as srrrction, or is deposited for mt'.elti'tii or grov-ih. The quantity secreted is directly as the quantity of blood 4.throVv'ri in, and irt'--e:^ely as absorption from the part, whim its- quail; -: ' decern'* part!* on that of blood tlirown in arm prt'y on tlie relative power ot" venous i;. i--'»-,:)u i.tick absorption in the part. Jn addition to these it;e nature m> v?hi\ is deposited innutrition and growth is mtiac.Kcd by the peculiar' irt tractions of each part, which exist frmn the prfrnordm::. o-i bem^. { V. OP TUB FCNCTIOrVS OF TITE MlrW, » ".'j. Sensation by tlie Receivers, Increase in the quantity of Turf! finished by any part to the brain, produces in the sou) or mmdr ,-f ie»ve" f'.r^- evatfirf! the ei^-pic sensation oi'*■;.<■:§ dco-iei..-'* in'-;:e i^ramHv,produces me- opposite sensation oiculd. Thirsiis a modi- fictition of this sense of heat m the stomach. Other sensations, from tlie slightest feeling to the most severe pain, are caused by stimulants producing a tendency to reflux in the brain, and are consequently con- «.rbuled by the circumstances already mentioned. (24) As the quantity of fluid necessary to counterbalance, is more hke- Iv to be made up without a reflux in the brain, the Anther it is remo- ved from that organ, it is plain that sensation must become more ob- scure and uncertain, in the same proportion. The bowels which are Punished from the semilunar ganglion can, on this account, scarcely be said to have couvmonfeeling at all. Sensation according to this explanation is diminished as fluid is re^ eeived into the nerve. Muscular contraction of course tends to des- troy it, and so does lymphatick absorption. The latter also, for simi- lar reasons, retards muscular motion, producing in the voluntary mus- t-Jos, the sensation of fatigue. But its effect in arresting sensation, is not immediate, because sensation is still continued while the lymph is passing through the celluiar absorbent, and is only checked as it ar- rives at the lymphatick gland and'it3 fibrin imparts fluid to the absor- bent receivers. The fluid of which the lymph is despoiled, then goes to supply the demands of the stimulus and supercedes that reflux in the brain on which sensation depends. From this cause it arises that sensation fias a tendency to intermission, n-ki.le the stimulus is cor tin- ned, as is more particularly observable in painful affections, such as cknlick, gripes, tooth-ache, fyc. The nerves subservient to scekg, smelling, and hearing* having no ipiniediateccrioection with absorbent n«rves, are of course not imole to be arrciBtea. in liicn functions, by ab- sorption. 33. Sensation by the Dischargers. The action of the receivers of the stomach being in. over-proportion to iha fluid furnished by its dischargers, produces the sensation of nausea, and if this condition is mcreased to a certain extent, violent cvhtrPA'tion or vomiting, ensues. On the contra, y when for want of food in the stomach on which the fibrin of the blood may deposite fluid, it refuses to receive more, as- it passes the muscular cells of the lunysin expiration, then the dischar- ging system becomes surcharged, producing the sensation of hicij<_'ht. The sold produces thought or reflection, by its pnv.er of stimulation in the brainy so as to create a demand for more fluid tnan e.un be supplied. Besides the iiu.etiona! serves of the f. aiti, which produce contraction and furnish fluid in oLediente to the will, there is one immediately connected with tho^e parts of tlie bram concerned in the higher operations of the mind. This is the -.'.. -or) d-urn of the seventh pair, which proceeding from the union cf :'-;e nous Varolii with the Mrrulla oblongata, and the dura eerebei- »>, c;'ott'e to aii ihuSO u«uj>clc3.»vhicij aiC. duec'lj; conciuiieu in fa-vie^. «.-$- ( *6J p»v>i»oir To the face, ftnd is consequently the basis uf physiognomic.._; distinctions. All these nerves by supplying fluid, arrest absorption and as thought like sensation is arretted by a reception of fluid suffi- cient to meet the demands of stimulus in the brain, it is evident thai when by muscular contraction absorption is arrested, until lymph is accumulated in the system in quantity sufficient to supply the whole demand in thehiaia, then thought ceases, oi in other words sleep j*-:* pcrvctieJ. § VI xsr DISEASES OF the huma:-; bcdv. ef.3. Inflammation, When a part is stimulated its muscular arteries con tract j and consequently an increase of blood is thrown into the cellular arteries. When the increase of blood thus thrown in, is so great as to produce stimulation itself, then we have a case al'simph: injlanunation. The lymph of the blood, yielding up its fluid to the neg- ative receiver, is accumulated and coagulated in the part, which con. seqtiently becomes hard and swelled. The cellular lymphatic! a of tho part being tightly compressed refuse passage to the lymph. Tl-a scrum somewhat modified accumulates, while the globules of mu;-v? lar fibre and coagulated fibrin successively robbed of their fluid, fa , come white globules. These together form^as and ptesunl us v.ita a case of abtefc^i Stimuli applied to any part of the body, by creating a demo d foe fluid & increasing the contractions of*the muscular vessels, pj'edispe* kjz 'o mfl uumation in other parts. ;j(3. , Fever. When miasm is breathed the receivers of the Junes ara stimulated, and carry off too great a portion of fluul from tiie mu.s- c.ihr cells. T.'iis produces such effects-as naturally arise from too larr.ro i proportion of fluid being furnished by the pulmonary receiver? to the third order of ganglia on the one hand, and too sparing a disrn- Initian offluid, by die pies tie of expiration, rn the otiier. Wfieu too I'-irga a portion of fluid is burnished by 'he pulmonary receivers, the quantity coe.veved by the receiveis of all the remainder of the t'ird crier, which are connected by equalizers, is proportmnably diminish- ed. 'Fiiis on tlie muscular fibre, by restraining contraction, w.ii pro- duce that eti'eet called debin\t/, must conspicuous in the heart. The power of the heart.'which should equal the. aggregate power of the muscular bloodvessels, is then no longer able to force a passage into the external vessels which retain their full contractility. The blood is accordingly forced from them into the heart and great vessels, pa: ticulariy those, which also, deriving their nerves from the third order, arc weakened and £>rced to receive it. An increased supply offluid from within now produces the sensation of heat or thirst, while a decreased supply from the external vascular fibres produces that of eu\>< p-o-ui ,'„;j",ch condition, this lus bcim called tho cold io'^v of fc.or, 'ttv: ri* ,t P.vnis'ied power with which the heart forces the blood to nisf^.nt £tr distr.-i.-dcn rends.« :':e bed; r.eo- ativo, produces a spasm of the extreme muscular vessels of the sur- face, as well as of the liver, and other intcriour organ's, and increa-esr iymphatiek absorption.- From the latter cans*--, pus is fd.-serrbec^arul ,.'.' .ourseab-'resses retreat. Bile is absorbed iV< m the bowels and eeS- tivenoss is produced. oIucb:;>- is abseil r-d fia-m 'be mine which new deposits no sediment. Mucus :s abse-hed from the bronchia, rrodu- mngu sr-n-e of lightness w'uh diy cer-".ii; The ^'.statesy r.ei ves-nt.-^' tluct particies of lymph, &i robbing rben.ief iLoh fluid, consolidate ilrun «•■ ori the papillae, producing the crusted tongue. A* these■ sr-pplic,-:, from absorption, are exhausted, tlie muscles in turn yield a partial"«?im- ply by small rapid alternate contractions, which constitute aihahe; or.. uk-some cases, by more violent & permanent contractions of part it: ;- hr muscles, constituting spasms or'cramps. From a want of fire usuir-l. press offluid from the dischargers on the stomach during expiraiien the appetite ceases, and as the receivers of the stomach gain ascenden- cy, this is followed by aversion to food, navsra and vomiting. Tho ~eils of the liver are not expanded for portal blood which is conse- quently arrested,and as by this route only, water reaches the circula- tion, the watery secretions, as urine, sweat, saii-va, &c. uje all dimin< ished. '". As the stimulus of distension increases, the- contractions of the «eart & great vessels become violent. Blooo is drierii into the extreme vessels, and the hot stage of fever is produced. TLl pulse is »ovv fuller & s'ronger, heat and redness of the sk.o :e:pervrne, thiis*, restlessness and headache, are increased, till the full quantity of fluid j's furnished, and the stronger stimulus, by yielding an increased sup- ply, begins to prevail. Morbid absorption now ce; ec-s, the crust dis- appears from the tongue, and- the extreme vessels are relaxed. Suppose the stimulus of distension, surpasses that of rnh?m,and ' transmits fluid enough to supercede that arising from its action, then the fluid carried off by the receivers of the lungs, will be again thrown i.ato its proper channel. It will, as before, he driven in ex) iralien ht she dischargers, to t!:e liver, the cells of which, give p;s~a^»- again, to- I he portal blood,' so that the aqueous secretions agoin appear. The -'organic!; fibres of the stomach and fibrin of the blood being a:.-ajn sura' ^lef:" t!ie-ae(:-jtitea:id;-dig:33t:o:>«e-."--r. As-tlie hearted vc5*.-H>.W- ••*.-« too nalns t-vve v;ay ami tcvor b'^-.tf triemGoiVcs ahd distension c v ' sir the present. .,v___As'scon as the disten- This is a paroxysm of intermittent fen ' -qg&e~ become* prcdom- sive stimulus cease*-, the miasmauek stimuli^ ""'" Uiis v\eak it may . iint and commences iis operations as before, i. "'h two or on- require.three days to.ienew its effects. If more power.> '-respy- ly one—being repeated at jiwrfiwi, tertian, or quotidian, pcriou. "^ lively, until the miasmatiek stimulus subsides. If the miasma.., stimulus is too powerful, to yield altogetherto the defensive stimulus, then the fever will only remit, and as the power of miasm increases the disease will approach the continued form. When the miasm ;t- iciv begins to surpass the distensive stimulus, the reaction becomes .more obscure or is altogether extinguished. Such is the case in ty. > phusgrador, ahd more particularly in what id known, in the South- em States, by l:.8 name of cold plague. '■\ VH. DISEASES OF THE 31'IXD. "7. The action of the mind on the brain in producing thought, is umdiiied by other stimuli, either on distant parts of the body, or on the brain itself. Any long continued stimulus, as that of distension, in dyspepsia, by contracting the muscular vessels of the brain, predis- poses to u.idije tulincssofitscellular vesseis,ontbeapplicationof mental stimulus. 'ritis exhibits, according to its degree, and the part stim- ulated, the various symptoms of Irritability, hypochondriac oj/retions, 'i.icljiultory. ami madness, and a stdl greater fullness of the vessels produces delirium. When the predisposition is caused by chemical stimulants conveyed through the circula'ion to the brain, the eflocts are exhiliration, intoxicaiion, 4'C which ceve with their causes. 33. llyspepsiz. When the causes which diminish the contrac- tors of the heart and^greal vessels, or increases that of the extreme vessels, is slowly applied and h.Lg coli.mued, it produces a habitual distension ofthe former. The symptoms arising from this chronic stim- ulus of distension, constitute the disease known by thi; various names *>f dyspepsia, liver eonplalat. or nerrous complaint. More or less Oi this stimulus of distension is found to prevail in most other chronicle ■4:s.o.!sej of the system. ,£ VIII. OF Tiro MODVS OPERAXOS OF MEDICINES. iVJ. Medicines talren into the stomach may be confined in their action, to the alimentary canal, or entering the circulation by veins or iymphaticks, according to laws already noticed, may act on other parts of the system. They may alter the circulating blood, a? iron, \\*m-h by increasing the red pro-tide.*, is a tottick. .They..may [ 18 J ' y easily receiving interstitial fluid, rob other particles of frVe-ir prope* quantities, and thusTrom their effects on the solids, they are denomi- nated astringents. Or they may stimulate the nervous system, with various effect, according to their quality and the structure of parts in which the stimulated nervous fibril terminates. When this is in secre- mg or glahdular structure, by contracting the calibre of the muscular arteries, they throw more blood into the cellular arteries, and thjus ■the secretions being increased, and altered, the medicines are s'od to oe dinretick, diaphoretick, sialagogue, fyc. When on the brain they are sedative, exhilarating, narcovck, Sec. When on the receivers of the lungs, as the blood passes through, the fluid which is otherwise disposed ot by the pressure of expiration is carried off', as by the stim- ulus of miasm from the muscular cells. Absorption, by the dischar- gers of the heart, is at the same time diminished, and hence the aque- ous secretions are increased, and the stomach and bowels being filled are stimulated to discharge their watery contents. These effects arise from tartansed antimony, neutral .salts, &c. which are conse- quently classes oiemeticlcs and catharticks. The stimulus of disten- tion will take place here as in the case of miasm, but in vornitiDg the pressure of the abdominal jnuscles assist the heart and great vessels to unload themselves, by which this stimulus is prevented, and the bile nnd other organized particles are permitted to flow and be discharged fn purging this does not take place,-and of course the discharge of bile is arrested as before explained. Medicines which stimulate the alimentary canal by increasing ov- iganick contractions and furnishing fluid to the fourth order, diminish "ts absorption, and consequently produce bilLuos d'scharges, such as calomel, aloes Jalap, and most of the vegetable bitters which are iut very slowly if at all absorbable. These constitute a rlass of xc- \articks known as anti bilious. The less rapid but more durable stimulants of this clasp, such a& ilnchona, columbo, gentian, Sec. are given to produce a more perma- •ent effect on the canal. When the stimulus ot distension exists, these medicines, by exciting increased contractions of fheorganic fibres, pro- duce a supply offluid to meet the demands of this stimulus of disten- 'ron. This suspends pain, and the inordinate contractions of the ex- treme vessels being removed, they again receive blood from tbe heart, and the circulation being restored to the surface, the system recov-rs ifsyrgor froin whirh these medicine-, constitute a class of to».*-hi FR-n ATA. The author not having had leisure, to cor- rect the proof, the reader will find, among ^ny errors in orthography & punctuation, the article Dyspepsia placed under "disea- esofthemind." ' It should have been n urn- bered (37) and placed at the clo^e ol the preceding Section. / 'HjK-;-::--^ rtnhs ij'ivi^.-ier- ■ :: -|:||it:::■ ;!-::'i::':-" ::'' !S^r S -,-V't;7 -I-' V-i'-'iti l-l'flffl ..... ' f';;ii |b:i? " - • -Vvil-