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his death, which took place Nov. 22, what has been cherished from our 1760, in the 77th year of his age. earliest youth.

In 1740, Dr Alfton published for Dr Alston's medical papers are, the use of his pupils, “ Index Planta "A Differtation on Tin as an Anfun præcipue Officinalium, quæ in Hor. thelmintic ;' " A Differtation on t Medica Edinburgenfi, Studiosis de- Opium ;' and “ A Case of extravasamonstrantur.8vo.

ted Blood in the Pericardium.” These In 1752, Index Medicamentorum are printed in the Edinburgh MediSimplicium triplex.” 8vo. pp. 172. cal Esays. 1. Alphabetical; the officinal names, In 1743, he discovered a property with numerous synonyms, from the in quick lime, which led him to bebeit botanical writers, pp. 118. 2. lieve, that the power of lime was not Oficinal names only; fossils, vege. exhausted by repeated affusions of tables, animals, in the order of bis water to the same lime; he adds, lectures. 3. Clallification of the offi- even for twenty or thirty times. The cinal names, according to the virtues; first notices of this paradox, as he beginning with the absorbents, and then called it, were communicated ending with vulneraries. A table of to the Royal Socie!y, and were printe the doses of emetics and purgatives. ed in the forty-seventh volume of the

In botany, Dr Alfton's chief per- Philosophical Transactions. This oformance wis, his “ Tirocinium Do pinion was contested, and drew him tanicum Edinburgence" 1753, 8vo. into a controversy with his friend and It contains a republication of his colleague, Dr Whytt. Having cona Index," first prioted in 1740; to tinued his experiments, and enlarged which he now added the “ Funda- his observations, he published, in mentu Botanica" of Linnæus. But 1752, his “ Dissertation on Quickthe bulk of the work is a profeffed Lime and Line Water;" republished attempt to explode the system of the in 1754, and in 1757 ; in which he Swede, and particularly to invalidate replies to Dr Whytt's Strictures; and, all his arguments for the sex of plants, after- enumerating a variety of disThis part of it was translated by him- eases, in which lime water has profelf, and published the next year in ved efficacious, confirms the opinion the first volume of “ Ellays and Ob- of his colleague relating to its lithonservations, physical and literary."" triptic powers. Svo. Could the doctrine of the sexes Dr Alston's Ledures on the Maof plants have been easily shaken, the teria Medica were prepared for the learning and abilities of Allton were press before his deceale, and were sufficient to have effected this purpose. published under the following title: But as it was not at that time sup- “ Lectures on the Alateria Medi. ported by hypothesis alone, so it has ca; containing the Natural History since gained additional strength, by of Drugs, their Virtues and Dores: new experiments, and found induc- also, Directions for the Study of the tions, resulting from them. Nurtu. Materia Medica ; and an Appendix red from his early years in the syf- on the Method of Prescribing. Pub. tems of Tournefort, Ray, and Boer. lished from the Manuscript of the late baave, to the first of which he had Dr Charles Allton, Professor of Boeven given improvement, it is not tany, and the Materia Medica, in the Strange, that, at an advanced age, Dr University of Edinburgh. By John Alston rejected a system of so much Hope, M. D. Professor of Medicine novelty, as that of Linnæus presented. and Botany in that University." In We do not willingly unlearn at sixty, two vol. 4to. 1770. pp. 544 and 584. O 2

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The first eleven lectures conlist of the manifold, and vaunted powers, preliminary discourses; on the rise attributed to numberless fimples, and progress of this knowledge ; on through almoft all preceding writers; the operation of medicines; of errors but on the contrary, will meet with concerning the materia medica ; on judicious doubts, observations, and exclasling simples according to their vir- periments ; yet, Dr Alston's Materia tues ; and some account of authors Medic.z must be considered, on the who have written on fimples.

whole, as exhibiting rather the stare In treating on each subject, after of it, as it has been, than as it is, in reciting the officinal name, aod the the works of Lewis, Bergius, Murprincipal fynonyma, the description, ray, and Cullen. It is but of late that and place of growth, Dr Alston gives, philosophers and physicians have exin his own words, the sensible quali ercised that degree of scepticiim on ties, powers, and uses of each simple; the power of medicines, which must after which follows, in the words of ever influence the mind, when expethe authors themselves, a copious de- riments alone form the foundation of tail of the opinions of respectable wri medical practice, ters, relating to each; concluding with : Were it within my plan to extend a recital of all the officinal compounds my observations, I should, with grateinto which each simple enters. Add ful pleasure, expatiate on the improto this, the reader will meet with a ved state of botany 4t Edinburgh, afvariety of collateral, and historical in- ter this period; when the zeal, and formation, which is highly gratifying abilities, of my much-honoured and to all such as wish to extend their en respected friend, the late Dr John quiries beyond the mere nomencla. Hope, assisted by the royal bounty, ture, and quality of each substance ; enabled him to raise the study of boand which could otherwise be acquia tany to an eminence uprivalled, unless red only from laborious researches. at Upfal, by any university in Eur

Although the reader will not find rope. the author giving implicit belief to

On Irritability confidered as a vital principle in organized bodies to

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THE discovery of the contraction establish it, and to defend it against

of the muscular fibre on the ap- physicians who attacked and opposed plication of a stimulus, or of what the it warmly. Wishing to understand immortal Haller called animal Irris more particularly this singular pro tability, ought to be considered as one perty of the muscular fibre, and disa of the most important that have been tisfied with what I have found in au. made in Physiology. It seems fur- thors relating to it, I underecok a prising that, though this discovery laborious investigation of the subject. was made forty years ago, no one has I began by making numerous experiundertaken to examine it more parti- menis with various poisons, the effects çularly. Perhaps the reason is, that of which on the muscular fibre I ate it was not favourably received by the tended to. I repeated and multipli. public at the time it was made, and ed these experiments, because I am that it has required thirty years to persuaded that it is only by the light

1 Journal de Physique. Par M. Girtanner M. D. de plusieurs Societées.

of experiment that we can penetrate traction, and mediately sensation ; into the sanctuary of nature, without that is, 10 ftimulus can act on the rik of bewildering ourielves. I owe nerve, but by the intervention of the much to the works oi Fo:atana ; and muscular fibre. When this latter has it is by following the footstep, of that lost its irritability, and is become eigreat philosopher often, by leaving ther paralytic or gangrenous, there them fomeuines, and by ihuvning the can be no sensation, although the conmistakes into which he has fallen, tiguous nerve should be perfectly that I persuaje myseif I bare found Sound. When, on the other hand, the truth. I fhall not here peak of by any accident the nerve is become the new views of the phyfio ogy of infessible, or has been destroyed, the the human body, and of discales muscular fibre will continue to conwhich immediately follow from the traci tipon the application of a stimu. resu'tz of my cxperiments, nor shall lus, but no sensation will follow, be. I enter into the detail of these espe. cause the connection betweçn the riments, because they will be related muscular fibre and the origin of the in a work I mean to publish in Ger- nerve is destroyed. Senlation and many next year. I shall only now moiion are, therefore, two properties give some detached propositions un- of organized inatter essentially differa accompanied with the proofs, which ent. Sensation is only a secondary may serve as a prospectus of my work, property which depends on the irriand which may attract the attention table fibre, and cannot exist without of some philosophers,

it. Irritability, on the contrary, is All organised nature is composed a primary property, ellential to the of folids and of fuids. The solid living irritable fibre, and absolutely parts of animals and of plants are dependent on the nerves. I know composed of three sorts of primitive that this proposition is contrary to fibres ; vize the earthy, the sensible, and the opinion generally received, whicis the irritable fibre.

makes įrfitability depend on the inThe earthy fibre forms the bones of fluence of the nerves. I too, adoptanimals, and the wood of plants. It ed this opinion, but manifold experia is inorganic, insenlible, in-irritable; ments have convinced me that it is is subject to no other laws than those erroneous, of unorganised matter, and has no life Not only does the irritable fibre þut in combination with the irritable act on the sensible and produce fenfibre.

sation, but the sensible fibre reacts on The fenfible or nervous fibre, is that the irritable and produces contraction which constitutes the nerves in ani. This is the cause of voluntary motions, mals. Plants are deititute of this spe, of convulsions, and of what are called cies of fibre : at least it has not as nervous diseases. The action of the yet been discovered in the vegetable nerves on the muscular fibre is in nokingdom. It is totally incapable of thing different from that of any other irritability or contraction. It is acted fiimulus, and I shall therefore call it upon only by the irritable fibre. Each the nervous stimulus. muscular contraction produces a The irritable fibre, improperly cal. change in the adjoining nervous fibre; led the muscular fibre, pervades all this change, in the living animal, organised matter. On it depends orreaches to the origin of the nerve in ganic motion, sensation, and even the brain or spinal marrow, and is life ; and on it the bodies that surcalled fenfa:ion. Thus every stimu- round it continually act by ftimula. Jus which acts on the living irritable ting it and forcing it to contract. It Ebre produces in it immediately con- is of this fibre that I am about to

speaka feat, ri be lays tbx ae te exced to the ation of electricity,

see otsze is ea i ise der:03 glas, ammoniac, musk, ... . .. But bare earr g 0:10, of aav o her ftimulus. The

4. cicat, i vi bent.2-. fcx paecote."- are observable in the 11.715 Dare, toate itt tabe be 0

sts, Oraiis fenfitiva, Dine * Ter 2,

0 0 0 210: es gisa, Hathrun arrans, &c. 217. C .cs. Its exis.cace is cas. Tie varts of trucurication especially ad azadly acmnitrad is air ais are rery iritable. Te ftamina oi wib w.12 D1201, 2.0 i fone that the ed aris, oi the Hekotrohare Co., 5.6, abas rozs, liza: sy 2:1, 0: t. Ceeduli, of the Ciftus titate Dots, eels, and fints. Sat.DTL, of the 1.11111 lupe bam, Iblis, woras, 20d Flos a.t not c: the Can., of the Forkorbea tena. bels erdo ned with i15.12.1v. Toe chi, ad effeveral others, contract friral tonigce of bonerties is exceed on the arsricain of a stimulus. The iogly Tiab, and contracts pua Agon.ts and puthis exhibit the same baini ulaed, ever after 'sing phenon.eaon. teen cur is pieces ana le arated from The elitence of the irritable fibre the an mal. The irritahüty of wifi io all org siled bouies being thus t 19, ci medu.t, and of pop, is prored, there ariles another queition, Well known. The naa ilus riesiium wel: worthy the a.tention of the phi. the botom of the lea to te lurface, lciupher. Is this irritable fibre the by alternately contracting and di fame, and subject to the same laws in dating its irritable fibres. The penú- every part of nature; or is it differ20t chrysalis of the papilis urtice is ently modified in different animals, very irritalle, efpecially for a few and in diferent plants ? Are effects days after its formation. The fin fimilar in appearance, produced by with which the caterpillar was co. different causes ? This problem is imvered, and which it has just quired, portant, but of difficult folution. In acts as a stimulus on the Dewly form the deduction of general rales from ed chrysalis, which is seen to contract fone particular phenomena, we are and dilate alternately, till the dried in danger of bewildering ourselves in skin falls off. Swammerdam saw the labyrinth of analogy, where to and figured the muscular fibres, and many talking phi olophers have lost observed their alternate contractions themselves, because they have preluand dilarations in the louse, and even med to enter it without the clue of in the fetus of a louse ioclosed in a experience. This has been my guide, microscope; others have observed and after repeated experiments and obe the same in other insects, and in mic- fervations, I confider it as demonftraroscopic animals.

ter', that the irritable fibre is the fame, The existence of the irritable fibre and subject to the famie luws, throughout in the vegetable kingdom, is proved all organised nature. This truth beby facts not less lingular. The leaves ing discovered, has presented to me of the Drofera rotundifolia and longi- an ample harvest, which the sickle of folia contract, when touched with the the philosopher has never touched. point of a pin, and dilate when the There are three kinds of irritable stimulus is removed. The leaves of fibre : the straigl.t, which is found in the Averrhoa carambola contract when the muscles of animals, in the leaves, touchcd, compreffed, or pierced. The stamina, and several other parts of Icaves of many species of Mlinofa, ef- plants ; the spiral fibre, found in the pecially those of the Minoja pudica, arteries, veins, lymphatic vessels, incontract upon being touched, or when tettines, and in general in all the vef

fels, fels, and cylindric or conic muscles as the solids. Their irritability conof animals and plants ; the circular lists in coagulability, and that coagufibre, or what we call the sphincters. lability of the fluids is subject to the

The straight fibre contracts in same laws as the irritability of the length or is shortened in contraction, libre. This is a new discovery, which the two ends approaching one ano- is the foundation of many important ther at the instant it is touched, or truths. any of its parts, by a ftimulus.

The degree of irritability in the The spiral fibre, in contraction, di- folids and Huids changes continually, minishes the diameter of the veñels and differs according to the age and which it forms. The contraction does system of the fame animal or plant, not take place at the same idstant and according to the sex, organisaa through the whole length of the fibre tion, and size, of the different indivias in the preceding, but is commu- duals. It is also accumulated by nicated succeslively to its different the abstraction of habitual stimuli, and parts. The contraction begins at the is exhausted by the application of place to which the stimulus is applied, stimulants, too frequently repeated or and is continued in the direction of too strong. We may remark three the ordinary motion of the fibre, to different itates of the irritable fibre, its terminarion. By this contraction, or three different degrees of irritabi. which is also called peristaltic motion, lity, of which it is susceptible. the fluids contained in the vessels are 1. The state of health. peculiar to impelled forwards, and circulation each individual, which I shall calt goes on. This circulation takes place the tone of the fibre. in vegetables, as well as in animals, 2. The state of accumulation, proand is carried on in both by the pe- duced by the abstraction of habitual riitaltic motion, which is the effect of Atimuli. the irritability with which the fibres 3. The state of exhaustion produ. are endowed.

ced by the action of too strong a The circular fibre when it contracts, stimulus, closes the opening of those vessels, at The fate of health, or tone of the the end of which it is generally pla- fibre, conlists in a certain quantity of ced.

the irritable principle, necessary to The irritable fibre, when separated its preservation, or in an equilibrium from the animal or plant, preserves between the acting stimulus, and the its irritability for some time, and con- irritability furnished by the lungs tinues to contract upon the applica- and the circulation ti tion of a stimulus. It even preferres When the sum of the iti muli acte this property, when cut into pieces, ing on the fibre is not strong enough as we may observe, by cutting the to deprive it of all its excess of irria fpiral tongue of a butterfly, or the ability, the irritable principle is acftamina of plants. All the pieces cumulated in the fibre, which is then still contract, which proves, that the in the state of accumulation : and {mal!eft portion of the irritable fibre stimuli produce contractions which poffesses its particular irritability, in-' are much tronger than when the dependent of the rest.

fibre was in tone. The Auids of animals, and of plants, When the lum of the stimuli, adiare endowed with irritability, as well ing on the fibre, is too great, the

fibre + I fall bereafter prove, that pure air is the principle of irritability; that this principle is absorbed by the lungs in respiration, and alterwards distributed through the fulcm by the circulation.

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