Chapter 17

"The name of GLISSON occupies an honourable place in the history of medicine, because to him we are indebted for the first elements of the physiological doctrine of the present day. Instead of directing his attention to movements alone, as the iatro-mathematicians, and even, to a certain extent, the animists had done, he referred to vitality all the phenomena of nature, of whatever kind, and attempted to reduce them to one, common principle. To this end he admitted, that matter is originally endued with forces inherent in it, and that living bodies in particular, are invested in their organs with a radical force, which, put in play by stimulants, whether internal or external, gives rise to all the phenomena of life. He even went so far as to assert, that sympathy may be explained by referring to the intercommunication of this force, to which he gave the name of irritability."

We shall also cite from SPRENGEL, a passage which throws some light on his theory.

"When they became unwilling, like DESCARTES and STAHL, to have constant recourse in their explanations, to the soul, they tried to find a philosophic proof of the existence of material forces, to show that matter, as mere matter, is endowed with particular forces, with which they might satisfactorily explain a great many of its phenomena. No one had hitherto sought for a similar proof; for ARISTOTLE had contented himself with an axiom, that all natural things contain in themselves the sufficient cause of their movement and rest. GLISSON and LEIBNITZ set themselves in search of this proof; but it was reserved for the immortal KANT to find it in the nature of matter itself.

"FRANCIS GLISSON may with propriety be considered as the precursor of LEIBNITZ. What he tried to demonstrate by scholastic subtlety, and by thousands of syllogisms, was developed by LEIBNITZ with a clearness and ability, which secured the suffrages, even of the unenlightened. Both of them went too far, in attributing life and sensation to matter, instead of claiming for it the two simple and primordial forces of attraction and repulsion.

"GLISSON sets out with the idea of substance, but he does not explain it with sufficient precision. Every substance has three substantial rudiments,--_fundamental_ substance, by means of which it exists,--_energetic_ substance, by means of which it acts,--and _additional_ substance, which determines its accidental qualities. All matter, as substance, must have an energetic substance or nature, which is the internal principle of movement. Therefore whatever moves spontaneously, and in virtue of an internal force, must _feel_ this motion, _and desire it_. All matter feels that it is, and that it exists by itself. It has therefore, consciousness of its own nature. Life consists in the activity of the internal substantial energetic nature. Death is the dissolution of the triple alliance of the internal energetic substantial nature, with the vegetative and animal natures, which two last belong to the _additional_ substance."[28]

In applying his theory to physiology, GLISSON'S idea is, that the fibres of the human body are endowed with a force, which he divides into three kinds; to wit, natural or inherent force, (robur insitum)--vital force, (robur vitale)--and animal force, (robur animale.)

Natural or inherent force, is a part of the constitution of the fibre, and is as much a property of its organization as are its tenacity, tensibility, &c. The sum of this force varies, in proportion as the constitution of the fibre is more or less perfect. It is strongest in athletic men and strong animals, and weaker in relaxed and debilitated persons. It may be compared with the contractilité de tissu of BICHAT.

The second, or vital force, is something superadded to the inherent sort. It is an _influxus_, derived to any fibre or set of fibres, from that greater sum of force, which arises out of a more elaborate, complex, and exalted organization. It varies in proportion as the vital spirits flow with more or less freedom; and in proportion as their quality is more or less perfect.

The third kind, or robur animale, may be supposed to depend on the organic constitution of the brain and nerves, and varies according to the state of that organization. We cannot help adverting to the resemblance between these two latter kinds, and the contractilité organique, and contractilité animale, of BICHAT; and this robur comprises, as we shall show hereafter, both the contractilité and sensibilité of the French physiologist.

GLISSON, in his chapter de Irritabilitate fibrarum, commences by remarking that a motive faculty existing in any fibre, unless it were of an irritable nature, would leave such fibre in one of the two following states: 1. It would either never cease from action, or 2ndly, being once at rest, its motion could never be reproduced; but the varieties and differences which we see in the actions of fibres, clearly demonstrate them to be possessed of irritability: i.e. if a fibre may be by turns in a state of action and repose, it is evidently possessed of a quality, whereby it can be induced to move if in a state of rest; this quality he terms irritable, or irritability. The next inference from this power of alternate activity and repose is, that the fibre is possessed of a faculty, whereby it can _perceive_ an irritation offered to it; but this perception of irritation further implies an _appetence_ for a change of its actual state, before the motion can really take place. Perception, appetence, and motion, make a triunit. "In the mean time, says he, as sensitive appetence, and sensibility, are frequently confounded with natural perception, in this irritation of the fibres," he divides it into three kinds, viz. Natural Perception, Sensitive Perception, and Perception regulated by animal appetency.

Natural Perception is that principle whereby a fibre perceiving any alteration offered to it, whether pleasing or displeasing, is excited either to accept that change, or to avoid it, and moves accordingly.

Sensitive Perception, is that kind, in which a fibre, perceiving a change effected in some other organ, is impelled ad aliquid appetendum, and to move conformably.

The third sort, or Perception regulated by animal appetency, is that in which the brain directs from within, such movements of the muscular fibres, as are requisite for the execution of any purpose.

"Some persons," says GLISSON, "may doubt whether there really exists a natural perception of irritation in the fibres; but we have elsewhere asserted in general the reality of natural perception, to wit, in my work, de Vita Naturæ; and whoever has known it, will readily admit this quality in fibres imbued with inherent, influent, and vital spirits. We do not expect, in this place, to establish it as a general principle; but if any proof, derived from a knowledge of the structure, uses, and actions of the fibres, can be adduced, it may be here attempted."

"It is indubitable that the fibres are alternately at rest and in motion; for, during sleep, they are all relaxed, with the exception of such as subserve the functions of respiration and circulation, and even these are by turns quiet and active. During waking again, they are all in a state of moderate tonic motion; and moreover, during all movements of the limbs, the antagonist muscles yield spontaneously, the abductors being active, while the adductors are relaxed, and vice versa. Hence it is manifest, that the fibres are alternately quiescent and active: but, since they are not _principal_ or sui arbitrii agents, it is necessary, in order to the new movement, that they should be irritated from some source: for, it is impossible that a fibre in repose, can be set in action without an irritating cause; nor can we conceive of a part being irritated without _perceiving_ the irritation. It is like speaking to a deaf man, or trying to awaken a dead one."

"If you say, fibres are possessed of sensibility, and can be excited by virtue thereof, I confess that they are sensible parts, and may thereby perceive some, not all irritating causes; but whether sensation excites them immediately, or rather, is transmitted to the brain, and irritates the animal appetency; and further, whether the animal appetence, effects a movement in them directly, and to what sort of perception this irritation may be properly and immediately ascribed, is detailed in order below, when we come to explain sensitive perception, and perception à phantasia imperata."

"Let us now go on to point out those cases, in which no suspicion of _sensation_ can be entertained. The pulsation of the heart is neither effected nor affected by sensation; its fibres, in virtue of the irritation occasioned by the blood in its ventricles, are excited to contract, and thus occasion the pulsation, but when the irritation is remitted they relax, and recover the natural state. Now it cannot be denied that this is an evident case of irritation of the fibres, for according as is the irritation, so is the rythm of the pulsation, which varies at times, as in febrile and other affections: nor is it right to pretend that there is any sensation in this case; because this perception of irritation _per vices_, is exercised as well during sleep, when the senses are all locked up, as in the waking condition. The fibres do not, therefore, _perceive_ in these actions by a sensitive, _but by a natural perception_, the irritation of the vital blood, which animates them to alternate contraction and relaxation. This is corroborated by those tumultuous irregular motions which continue in animals after decapitation; so also the intestines when still warm in a recently opened animal, move and twist about; the muscles in dead animals also, excited by the perception of cold, contract with a strong tonic movement, and render the body rigid. The hearts of some animals too, when torn out of the body, and even when dissected, continue their endeavours to pulsate. Is there any further evidence wanting? We may hence infer with sufficient confidence that the fibres (without the aid of the senses) may _perceive_ irritation, and move themselves conformably."

In the next place he examines the nature of sensitive perception of fibres, and goes on to show how an impression made on an external part, or a natural perception, becomes converted into sensation, and thus made known to the sensorium. But his disquisition is not only very long but very dark, and we shall therefore pass it by with the exception of the following.

"Natural perception includes within itself a _rationem positivam_, and a _negationem formalem_.

"The ratio positiva is the perception of the idea, or image of the object moving or changing the fibre.

"The negatio formalis is a denial or refusal to communicate this image to the sensorium. In the process of transformation into sensation, the positive ratio is not changed, but remains the same, and is the first part, or basis, both of internal and external sensation.

"The negatio formalis is destroyed or abolished in any case of impression communicated to the sensorium. Natural perception, in its ratio positiva, is not abolished or degraded by being converted into sensation, but is rather exalted, or gifted with a more dignified nature. By as much as public or general knowledge is preferable to private, or public advantage to that of an individual, by so much is sensation preferable to natural perception. Hence nature formed so many organs of sense, that the phantasy might have notice of what ought to be done, desired, or avoided."

He does not doubt that external sensibility is inherent in the nervous parts of the external organ, whence he infers that it may readily incite the fibres of such organ ad appetendum et movendum; for, as external sensation is communicated to the brain by means of the nerves, it must of necessity be true, that these nerves and nervous parts (such as the fibres,) are the subjects of it. Since then sensibility causes its subject to feel, it consequently enables it to desire and move comformably. For perception in any subject is vain, unless it can desire, and appetence is useless, unless it can move. External sensibility, therefore, may be said to render the fibres _actu irritabiles_, for example, as often as the irritating cause is perceived; but as the irritation is perceived, not by a sensibility, but by a mere natural perception, this it is which constitutes their irritability.

Thus we may perceive that the triunit consisting of perception, appetence, and motion, constitutes the celebrated irritability of our author. But he has been too latitudinarian in his application of the theory; for he did not limit it, as HALLER has subsequently done, to one sort of fibres, or indeed to fibres alone, for he says in cap. IX., "It is to be remarked that natural perception belongs to other parts of the body besides fibres; to wit, to the parenchymata, bones, marrow, fat, blood, recrementitious juices, humours of the eye, and such like, all which are irritable, and increase the irritable constitution of the parts, but these parts hardly admit of the existence of animal perception." HALLER blames GLISSON for having gone so far in his application of the theory, and it is well known that he himself restrained it to the single tissue of muscular fibres, and denominated it vis insitum, or inherent force; whereby he distinguished it from his vis mortua or elastic contraction, on the one hand, and the vis nervosum or voluntary power, on the other; the former being something less, and the latter something more than irritability. GLISSON'S theory, when fully explained, which we cannot for want of space do here, will be found to bear a very strong resemblance, in many points, to that of BICHAT, who has invested the matters of the body with vital powers, far beyond those attributed by HALLER; and as we are not furnished in the present article with sufficient space, we hope in some subsequent number, to place this matter in a plainer light before our readers. In the mean time we may remark, that GLISSON seems to be the first of those who have placed the subject fairly before the medical public; for although faint traces of a similar theory may be perceived before him, especially by translating terms into their equivalents, yet he has the merit of using a term which, in spite of all subsequent modifications, is in daily use.

GLISSON'S latitudinarianism may be contrasted with HALLER'S rigid application: for the latter says, "I call that an irritable part of the human body, which on being touched by a foreign body, renders itself shorter;" thus while GLISSON attributes his triunit of perception, appetence, and motion to all the tissues and fluids, HALLER confines it to muscular fibre alone. No one can doubt that the membranes of the body are endowed with vital properties, but yet they do not shorten themselves on being touched by a foreign body. BICHAT has distinguished their vitality as organic vitality, and the contractile qualities displayed are divided into insensible organic contractility, and into contractility of tissue: but these sorts of contractility mount up by insensible gradations. He says, that "entre la contractilité obscure mais réelle, necessaire a la nutrition des ongles, des poils, &c. et celle que nous presentent les mouvements des intestins, de l'estomac, &c. il est des nuances infinies, qui servent de transition: tels sont les mouvements du dartos, des arteres, de certaines parties de l'organ cutané," &c. We will close with a comparison between GLISSON'S irritability, and BICHAT'S contractility. At page 70 of the Treatise _sur la Vie & la Mort_, BICHAT supposes that a "muscle enters into action, 1st. by the influence of the nerves which it receives from the brain, and this is a case of contractile animale," (which differs in no respect from perception regulated by animal appetency of GLISSON). 2ndly. According to BICHAT, the muscle enters into action "by the excitation of a chemical or physical stimulant applied to it, and which artificially determines a movement of the whole muscle, analogous to what is natural to the heart, and other involuntary muscles. This is sensible organic contractility or irritability," and corresponds to the sensitive perception of the old English physiologist. In the 3d place it enters into action by the stimulus of the fluids which circulate in it, and this is insensible organic contractility or tonicity of BICHAT, and is nothing different from GLISSON'S natural perception. BICHAT makes a fourth case; as for example, when a muscle is divided across, it contracts by a _contractilité de tissue_, or _par defaut d'extension_. We do not perceive how GLISSON'S natural perception can be applied to this case, but he treats of it in his fifth chapter under the head of Cessatio: it is that state to which a fibre is reduced when left to itself, and freed from all stimulus.

BICHAT has attributed to some fibres the power of active elongation. On this subject GLISSON says, "Impossible enim est, ut simplex fibra, sua sola actione, se secundum longitudinem distendat, nec modus quo hæc fiat concipi nedum effari queat non negavero quin in distensione hac, aliqualis fibræ actio includatur, sed ea tota contractiva est, & distensioni ab extranea causa factæ reluctatur." A doctrine as sound as that of the 47th proposition; a doctrine too, without admitting which, we think no man can understand the theory either of simple inflammation, or of the febrile affections. We hope to resume this subject at an early period.

FOOTNOTES:

[25] Hæc ei generatim videbantur, ex igne omnia constare eodemque interire. Diogenes Laertius.

[26] Quatuor æternus genitalia corpora mundus Continet; ex illis duo sunt onerosa, suoque Pondere in inferius, tellus atque unda, feruntur, Et totidem gravitate carent, nulloque premente Alta petunt, aer atque aere purior ignis.--OVID--_Metamorph._

[27] Lib. de Carnibus, HIPPOCRATES says: Quod Calidum vocamus, id mihi immortale esse videtur, cunctaque intelligere, videre et audire, sentireque omnia, tum præsentia tum futura: cujus pars maxima cum omnia perturbata essent in supremum ambitum secessit; quod, mihi veteres æthera appellasse videntur. Altera pars locum infimum sortita, terra quidem appellatur, frigida et sicca multas que motiones habens, et in qua multum sane calidi inest. Tertia vero pars medium aeris locum nacta est, calidum quid existens. Quarta pars terræ proximum locum obtinens humidissima et crassissima. His igitur in orbem agitatis cum turbata essent, calidi magna pars alias in terra relicta est, partim quidem magna, partim vero minor, alias etiam valde parva, sed in multas partes divisa. Et temporis successu a calido resiccata est terra, ista in ea tanquam in membranis contenta circumse putredines excitant, ac longo tempore incalescens quod quidem ea terræ putredine pinguedinem sortitum est et minimum humidi habet, id citissime exustum ossa produxit. Quæ vero naturam glutinosiorem sortita sunt et frigidi communionem habent, ea neque calefacta exuri potuerunt, neque etiam humida fieri ideo formam longe ab aliis diversam nacta sunt et nervi solidi exciterint, cum non multum in iis frigidi inesset. At venæ frigidi multum habebant cajus pars circumcirca ambiens et quod erat glutinosissimum, a calido exassatum membrana extitit. Quod vero erat frigidum, a calido superatum, dissolutum est ideoque humidum evasit.

[28] K. SPRENGEL, Hist. de la Medicine.

QUARTERLY SUMMARY

OF MEDICAL AND SURGICAL INTELLIGENCE.

I. ANATOMY.

1. _Papillæ of the Tongue._--At the upper surface of the tongue, say MM. LEURET and LASSAIGNE, in their recent work on digestion, the mucous membrane presents projections of three different species; and these are, the sensitive papillæ, the epidermoid papillæ, and the mucous cryptæ. The sensitive papillæ are numerous. They occupy the anterior four-fifths of the tongue, on which they are implanted by a narrow pedicle. The rounded head of these papillæ is much more prominent in the living subject, than after death; but injections are capable of restoring them to their pristine form. Nervous fibres from the lingual branch of the fifth pair have been distinctly traced to their roots. These papillæ are of various sizes; at the root of the tongue they form a V. They are all vascular and nervous. The sense of taste is referred by these writers almost exclusively to the above papillæ.

The epidermoid papillæ are of a nature similar to those retroverted prominences so remarkable on the tongue of the cat; as well as in the lion, and some other animals. They are larger in many species than in man, and, in general, the sensibility of the tongue appears to diminish in proportion to the remoteness of the subject from the human structure. The epidermoid papillæ are separated from the tongue along with the epidermis, or rather, epithelium, by maceration for a few days in vinegar. They are pyramidal in form. They are grouped round the sensitive papillæ, except on the edges and point of the tongue, where they are rare. Their base is perforated, and always gives outlet to a crypta. In an epithelium separated from the tongue, these minute and numerous perforations are easily distinguished from the larger ones left by the sensitive papillæ.

The office of the epidermoid papillæ appears purely mechanical.

The only cryptæ which produce, of themselves, a visible projection on the surface of the tongue, are situated at its base. They are formed by the mucous membrane, like other cryptæ, and are scattered between the sensitive papillæ.

In the tongue of birds, there is always a bone or cartilage; and the external membrane is dense. In reptiles the tongue is soft, possessed of little sensibility, and capable of great elongation. In fishes it is endowed with little motion, and is often wanting.--_Bulletin Medicale._

2. _Villi of the Stomach and Intestines._--MM. LEURET and LASSAIGNE state that the villi can be easily injected; most conveniently from the vena portæ, though the arteries may be employed. In the latter case, the matter of injection is effused into the intestinal or gastric cavity. The villi are peculiar to these parts; they are inversely conical, adhering to the membrane by their smaller end. The best mode of exhibiting them, is to tie the vena portæ of a living animal, when they erect themselves by the afflux of blood. These diminutive organs, about 3/100 of an inch long, then exhibit distinctly, under the microscope, four red longitudinal lines, being probably vessels.

Injections made retrograde from the thoracic duct, pass through the villi into the intestines. When the stomach of a man, who died of some complaint not deranging its condition, is examined, we sometimes find its lining membrane covered with a multitude of minute white points. These are the villi in a flaccid state. In those who have died during digestion, they are erected, and of a rosy colour.

When the intestine of a living animal is examined under a microscope, after being carefully washed, a great number of orifices are seen, from each of which exudes a minute drop of a transparent fluid. These rapidly disappear; and then the villi attract attention. What these foraminula are, the reviewer, M. DU FERMON, does not tell us.--_Ibid._

3. _Minute distribution of the Vessels of the Liver._--M. CRUVEILHIER gives, in his lectures, an account of the results he has obtained from a minute injection of the liver. He finds, 1. The acini surrounded with a dense, cellular texture, paler than themselves; 2. The ramifications of the hepatic artery distributed to this cellular envelope; 3. Those of the vena portæ spread around the acini, or granulations of the liver; and 4. Those of the biliary ducts, and of the hepatic veins, emerging from the cavities of these bodies.