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LEEDS SCHOOL OF MEDICINE.SIXTEENTH SESSION, 1846-7.

The Session will commence on Thursday, October 1st, 1846.

Anatomy, Physiology, and Pathology: Mr. T. P. Teale, F.L.S.,Mr. Nunneley, Mr. Ikin, and Mr. S. Hey.

Anatomical Demonstrations: Mr. Price, Mr. Radcliffe, andMr. Staniland.

Principles and Practice of Surgery: Mr. W. Hey and Air.Garlick.

Materia Medica and Therapeutics: Dr. Pyemont Smith, andDr. Heaton.

Chemistry: Mr. Morley and Mr. West. -

Principles and Practice of Physic: Dr. Chadwick. °

Midwifery and Diseases of Women and Children: Mr. Smithand Mr. Braithwaite.

Forensic Medicine: Dr. Pyemont Smith, in the summer.Botany: Dr. Heaton, in the summer.Operative Surgery in the summer months. ,

Clinical lectures will be given at the General Infirmary, onmedical cases, by Dr. Hopper and Dr. Chadwick.On surgical cases, at the General Infirmary, by Mr. Smith,

Mr. W. Hey, and Mr. T. P. Teale.Also on ophthalmic and aural surgery, at the Eye and Ear

Infirmary, by Mr. Nunneley and Mr. Braithwaite.

ON THE MUTUAL RELATIONSEXISTING BETWEEN

PHYSIOLOGY AND PATHOLOGY,CHEMISTRY AND PHYSICS,

AND THE METHODS OF RESEARCH PURSUED IN THESE SCIENCES.

BY BARON LIEBIG.

Rise and Progress of the Natural Sciences.THE history of the natural sciences teaches us that every

especial department or branch of our knowledge of Nature isconstituted at first of a number of observations and facts, theresult of experience, having no discernible connexion or

obvious relation to one another.

Special laws of Nature.The discovery of certain facts which connect two or more

of such original detached observations, supplying, as it were,connecting links between otherwise disconnected phenomena,led to the apprehension, first of special laws, and subsequentlyto the deduction of general laws, or, what amounts to thesame thing, to the invention of certain terms expressive ofthe mutual dependence or connexion existing between amore or less considerable number of natural phenomena.

General laws of Nature.

Many branches of natural philosophy-mechanics, hydro-statics, pneumatics, optics, acoustics, for examples-becameelevated to the rank of sciences, when it was demonstratedthat all the known instances of the phenomena of motion,whether of water, air, light, or sound, are referable to certainabstract truths-i. e., a small number of indisputable facts,which serve, not only to connect all the observed phenomena,but which also necessarily comprehend the elucidation ofevery possible fact left for future discovery, so that, in orderto explain any new phenomena, it is not necessary to institutea new series of experiments, or to go over the same groundsof reasoning and deduction as at first.

If we may assume it to be indisputable, that not only thephenomena of inanimate matter, but also those which arepeculiar to living vegetable and animal forms, stand in certaindefinite relations to each other-i. e., are dependent uponcertain necessary causes; and further, if. it be true that aclear and satisfactory insight into the nature of organic changesand processes can be obtained only through the medium of ajust apprehension of these causes, it must be concluded thatthe investigation and elucidation of the relative and mutualposition of dependency in which the phenomena of livingmatter stand to each other; in other words, of the causes andessential conditions of phenomena-must be considered thehighest and most important aim of physiology.The simple knowledge of the relation of cause and effect,

or antecedent and consequent, amid natural phenomena,suffices, in many cases, to furnish a satisfactory explanation of

them. These relations are discoverable in every branch ofnatural science; increased and enlarged experience, accurateobservations, and correct experiments, will finally lead to a

perfect elucidation of phenomena and their causes. It cannot,therefore, be questioned that, as chemistry, at a certainpoint of its progress, advances beyond the limits of a mereexperimental art, physiology is susceptible of being raised tothe rank of a true inductive science.

Order of proceeding in the investigation of Nature.If it be essential to the systematic course, or order, of in-

vestigating Nature, that our apprehension of special laws mustprecede that of generallaws,-if to attain to a correct con.ception of life it be necessary that we should know, not onlythe form of every part of every living organism, but also beaccurately acquainted with the functions of every organ, themutual relations and dependence they bear to each other,-the relations between the form and the matter of which everyorgan consists,-the manner and degree in which the formdepends upon surrounding parts, it cannot be denied that weare still at an infinite distance from the final deduction ofthat universal and ultimate term which is to comprise thetrue conception of life-the comprehension of the cause andlink of connexion of all its phenomena.Nay, so distant are we from the attainment of this exalted

generalization, that the probability or possibility of the dis-covery of such universal laws in physiology is by manv heldto be utterly inconceivable; indeed, the majority of physio-logists seem unable to conceive of the psychical apart fromthe corporeal phenomena of life, the vis vitce as distinct fromthe form and matter of the living organ !

Preconceived notions impediments to investigation.There is an infirmity attaching to the human mind, depen-

dent upon certain laws which govern its perceptive faculties,from which even individuals possessed of the most excellentunderstandings are unable readily to emancipate themselves.When daily observation has, during a long time, presented twoor more phenomena in intimate connexion, when we find theyhave been for centuries observed and regarded as inseparable,’when no one has, either intentionally or accidentally, been ledto contemplate them separately, the human mind almost losesthe faculty of disassociating them; and the reason seems torevolt at the conception, when first presented to it, that thetwo facts, or phenomena, are really and distinctly separable.Innumerable instances might be adduced to prove this

general truth. Many of the wisest and most sagacious menhave considered certain facts or views as impossible, simplybecause they were under the influence of this prejudice, andcould not apprehend them; whilst the next generation havenot only admitted the same notions to be perfectly conceivable,but, far more remarkable, they have been subsequently adoptedby all men as established and indisputable truths.Men of the highest order, most distinguished for intelli-

gence, and far above the influence of vulgar prejudices, werefor a long time incapable of conceiving the force of gravityas acting upwards as well as downwards, or that the sun, atsuch an immense distance, could exercise any action upon theearth, or the earth upon the moon. The great LEIBNITZ him-self rejected the NEWTONIAN theories, because he deemed themotion of the heavenly bodies in curves around a commoncentre to be impossible, without the agency of some con-tinually propelling mechanism, or of an angel specially ap-pointed for the task. He assumed that it was in accordancewith a natural law that if a body, like a planet, were left tomove unassisted by some controlling power, it must deviatefrom the circular course, and pass off in the direction of thetangent.The Newtonian theory of gravitation, the operation of the

force of gravity through immense distances without the inter-vention of material agents operating upon innumerable worlds,is now familiarly apprehended by every school-boy; never-theless, it was for a long time rejected by philosophers as acreation of the imagination, because they had adopted asan axiom that bodies cannot act at distances on each other,and they could not divest themselves of this prejudice.Many of the established laws of mechanics and other

branches of physics, which we know to be the fruits of long,patient, and arduous labour and inquiry, appear so self-evidentand obviously true, that if we disregard the history of theirslow and gradual development, it seems altogether incon-ceivable, how any individual could at any time have questionedtheir truth. The simple proposition that a body once put intomotion may continue to eternity to move in the same direc-

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tion and with unaltered velocity, unless retarded by someequivalent external influence, seemed so contrary to the mostcommon observations and self-evident notions, that the reco-gnition and establishment of its truth met for a long timewith the strongest opposition.The notion that two chemical substances, possessed of defi-

nite properties, should, by their combination in indefinite oruizlimited proportions, be able to form a compound of definiteand invariable properties, seems absurd. It is wholly incom-patible with, and contradicts all that are now considered to be,sound and correct views of chemical combinations.Thus it will be evident that the apprehension of a natural

fact or phenomenon is not dependent upon its own evidence,but that it depends altogether upon the intellectual standardof the observers. On the discovery of a new fact, if the in-tervening link connecting it with the habitual train of ideasand reasoning is wanting, men look upon the new fact as in-comprehensible or illusory. This is one of the greatest impe-diments to the application of chemistry to physiology, indeed,it renders the mere mention of chemical discoveries repulsiveto physiologists. And if, added to this, we consider the stateof pathology; if we contemplate pathologists assuming assureand undeniable, facts which rest upon no better foundationthan the faith of their forefathers in their truth, and observethat the methods of inquiry and of reasoning pursued in thisscience remain altogether unchanged, it must be confessedthat little hope can be reasonably entertained that chemistry,notwithstanding all its advancement, will afford natural assist-ance to physiology and pathology. But it is neverthelessabsolutely certain, that without the cooperation of chemistryand physics, it is impossible physiology and pathology can be-come worthy of the name of sciences, can have a true scien-tific foundation. Even amongst those who perceive the ne-cessity of this cooperation, it is a matter of doubt and disputein what manner and by what means it can be accomplished.

Physiology an Inductive Science.The proposition that every empirical science (and therefore

physiology) may in process of time attain to the rank and dig-nity of an inductive science, requires no further demonstration.Whether, or to what extent, the aid of other sciences may berequired for the attainment of this object, is indeed a matterof indifference. Astronomy has now become merely a branchof mechanics, but it owes high scientific character and founda-tion, precisely to this alliance.

Natural Laws.

If we bear in mind that, like every event in the world, soevery manifestation or change occurring in Nature, whetherin inanimate matter, in plants or animals, stands in direct re-lation to, or is the immediate consequence of, another phe-nomenon that has preceded it, every state or condition of aplant or animal body existing at any moment having beencaused by, and being dependent on, certain precedent condi-tions, it is obvious that if we know all the causes which haveproduced the present state, and are acquainted with theirpowers, and the effects, according to certain laws, they produceboth in time and space, we are able to anticipate and foretellthe state and condition which will next follow. The generaldeduction from these relations of antecedence and consequenceis termed a natural law.

Modern Chemistry as contradistinguished from theChemistry of the Past.

Every one conversant with the rise and progress of chemistry,and of the various branches of physics, must be aware that theadvancement of these sciences in modern times is attributableprincipally to the idea, which was gradually conceived and slowly admitted, that everynatural phenomenon, every state of,or change occurring in matter, in a word, every effect is pro-duced by several causes; and it is simply the patient investiga-tion of these causes, and the separation and discrimination ofeffects, which distinguishes the chemistry of the present dayfrom the chemistry of the past. In the days of phlogiston allinquiry was arrested by assumptions. Thus there was held tobe a principle of dryness, humidity, heat, cold, combustibility,metality, acidity, volatility, colour, state. For every propertyobserved a peculiar essence was imagined, which explainedeverything; the mere designation of a phenomenon was con-sidered a satisfactory explanation.The change of weight which bodies manifest when subjected

to chemical processes, was regarded as a simple property ofmatter, and also the effervescence of limestone with acids.The chemists had this theory ready for the phenomena of

combustion. They regarded the changes in weight whichthey observed, to belong rather to the natural philosopher toexplain, than to themselves ; they left it to him to say how asubstance could become heavier by the loss of one of its con-stituent elements. The increase of weight observed to followthe process of calcination was an accidental property, belong-ing, amongst other substances, to the metals.

Physiologists of the present day.Many of the physiologists and pathologists of the present

day are precisely in the condition of the phlogistic chemists,in their mode of apprehending and explaining the vital pro-cesses and phenomena. They ascribe the phenomena of thenervous system to a nervous force. Vegetation, irritability, sensi-bility, action and reaction, simple effects of motion, resistance,causes of the formation and changes of form, which are com-prised by them in the general term typical forces, these gentle-men look upon as distinct things or beings, or at least theyoccupy in their bearings the place of the essences of the phlo-gistic school in the explanation of phenomena.

Canfountling of Cause and Effect.The most common phenomena assume, in the minds of phy-

siologists, even at the present day, the appearance of particularfaculties. They explain them by supposing the existence ofspecial causes differing from all others with which we are ac-quainted. Thus, the restoration of a state of equilibrium be-tween two fluids, differing in their specific gravity, or twosubstances dissolved in dissimilar menstrua, and separativefrom each other by animal membrane, has received the namesof endosnaose and exosmose; and these names are treated as ifthey were distinct entities, and comprised a full explanationof the process they are intended to indicate. The pheno-menon in question is simply filtration; differing from ordinaryfiltration only in this, that the passing of the fluids is causedby the attraction of affinity instead of by pressure.To this mode of viewing and explaining phenomena was

added, during the reign of the phlogistic school, the no lesgrave error of assuming that causes must necessarily be simi-lar to their effects. Thus, something combustible must tethe cause of combustibility ; something intrinsically acid, cfacidity. The causticity of calcined lime was considered to bea separable causticum, transferable from one body to another;from lime, for instance, to the mild alkalies. A primitivealkali was supposed to exist in the alkalies, a salt in the salt!?,and a universal acid in acids. Analogous substances weieregarded as simply varieties of one and the same prototype.

Fallacious Explanations of Physical Properties.Many physical properties of a substance were supposed to be

explained, by the imaginary nature, properties, and physicaltexture of its molecules. Pungency of taste was ascribed topointed particles. Leming’s notion, that the ultimate particlesof an acid had lancet points, bent like tenter-hooks, and theatoms of alkalies being like sponge, blunted the acids, metwith universal approbation, as it seemed satisfactorily to ex-plain the neutralization of acids by alkalies.The precipitation of gold from its solution, by ammonia, was

perfectly intelligible to Leming’s contemporarieg. Ammoniahad the power to break off the points from the lance-shafts.It acts, says Leming, like a club which is thrown at a walnut-tree laden with fruit. In the same way of reasoning, sub-stances having an astringent or cooling taste were assumedto have an astringent or cooling action on the living organism,and liquids, such as alcohol, being said, in common parlance,to be strong, were supposed to have a power of impartingstrength when taken as medicine internally.

It is a mistake to suppose that this way of viewing and ex-plaining natural phenomena belongs to a time long past. Thefollowing passage from " An Attempt at an Universal Physio-logical Chemistry," published in 1844, will prove that it stillobtains among physicians of the present day:—" We conclude,therefore, correctly," says its author, M. Mulder, "that ana-logous forces exist in sulphur, selenium, chronium, and man-ganese, and we are thus led naturally to assume, that chemicaldeportment of these elements is independent of their materialform and condition, but, depends upon the forces which governthe molecules of the sulphur, selenium, &c. Thus the ideawhich represents to our mind the element sulphur, becomesassociated with the notion of a force, and this, of the sameforce which is also active in selenium, and which operates notonly in the production of compounds, but assists also in thedetermination of the principal characteristics of these com-pounds. This sulphur and selenium force is still manifest,

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even in the most remote compounds formed by these elements,&c., &c."

It will be seen, from this passage, that Mitscherlich andKopp’s beautiful researches on isomorphism have been unableto remove the impression made by that peculiar mode of ap-prehending natural phenomena which I have described.

Every natural phenomenon is occasioned by more than one cause.The correctness of theoretical expositions, or mere opinions,

may be questioned or discussed, and whether rightly or

wrongly decided on is a matter of indifference. But a pheno-menon perceptible to the senses at all times and in all placescannot be disputed. The cause or causes producing the per-ceived effects may be a matter of discussion, nevertheless, inthat field of Nature treated of by physical science, the imagina-tion, alone, being inadequate to the discovery of causes. We eknow that one and the same effect-as, for example, mechanicalmotion, a pustule on the skin, contraction of a muscle--may beproduced by many and various causes; on the other hand, oneand the same cause may produce as many and various effects.

Chemical Combination.

We know that every case of chemical combination, simpleas it is, depends upon at least three causes or essential condi-tions-namely, affinity, force of adhesion, and heat, whichthree causes must stand in a certain relation to each other,and exercise an equal share in the process, if combination isto take place.

Different Effects of Heat.We know, also, that when a given amount of heat expands

a solid body, merely forcing its molecules further asunder,twice or thrice the same amount of heat totally alters its pro-perties, and that a further change in its properties ensueswhen the amount of heat reaches a certain point.

It is absolutely certain that expansion, liquefaction, and the I’assumption of the gaseous state of bodies, are all produced byone and the same cause. But we also perceive that the effectsproduced are not in proportion to the cause. To explain thiswe are obliged to refer to a certain other cause, resisting orcounteracting the influence of heat-namely, the force of co-hesion. It is precisely from the investigation of this thatour notion of the force of cohesion has acquired a scientificbasis.The same heat constituting an essential condition of the

combination of one constituent of the atmosphere with mer-cury, when raised by a few degrees, produces precisely theopposite effect-namely, it effects the separation of the oxygenfrom the mercury.By a simple process of oxidation, we produce acetic acid

from alcohol. The same acid is obtained by the oxidation ofsalicylite of potass. It may be also equally produced fromsugar, wood, and starch, by the mere application of heat, withthe exclusion of all atmospheric oxygen. In all these cases,the product is the same, but the conditions of its formationare exceedingly different.Discrimination between the Effects of Vitality and their Causes,

the Principal Condition of Progress in Physiology.If it be true that a scientific basis for physiology can only

be laid by a complete investigation of the sum total of all theconditions upon which the phenomena of life are dependent,and that the primary task of the physiologist must consist inthe discrimination of the effects of vitality and the causes pro-ducing them, it is obvious that since many causes cooperateto produce these effects, he must have a perfect acquaintancewith all the forces and causes which are capable of producingin nature any motion of change of form and condition ofmatter. How otherwise could it be possible for him to sepa-rate the effects attributable to these causes, from those whichare referable to a cause having nothing in common in itsmanifestations with gravity, affinity, &c.

Principles admitted, but not strictly applied.No one can deny that these principles of investigation begin

to obtain an influence in the pathology of the present day;indeed, the difference between the method of viewing andinterpreting phenomena now prevailing, differs exceedinglyfrom the philosophic method which preceded it. But theinfluence of the latter is by no means vet obliterated; at allevents, not in Germany. Notwithstanding the full acknow-ledgment of the principles of exact research, the physiologistand pathologist too readily throw aside its control, and inevery case where their way is not clear, their unfettered

imagination plants a forest of errors in their path, and thusobscures and impedes their apprehension. The antithesesand periphrases, which were formerly so much in vogue, con-tinue to this day to play a principal part in all explanations,and deprive the description of the commonest facts and phe-nomena of that simplicity and clearness of which they aresusceptible. The error lies, not in the absence of just prin-ciples, but in the neglect of their rigid application.

‘

Examples in illustration.A few passages, quoted from the writings of a distinguished

pathologist of the day, (Henle, " Pathological Investigations,"Berlin, 1840,) will serve to justify the foregoing assertions,and to illustrate the influence of the old method of investigatingand interpreting Nature upon the doctrines of the presentday. They will show how small is the chance of arriving atcorrect conclusions when starting from modified and vaguenotions, and how little Science can gain, even from the mosthighly intellectual persons, if they do not avail themselves ofthe aid of chemical and physical truths.

ON

INFLAMMATORY ULCERATIONOF THE

CERVIX UTERI DURING PREGNANCY.AND ON ITS INFLUENCE AS A CAUSE OF ABORTION.

BY J. HENRY BENNET, M.D.,MEMBER OF THE ROYAL COLLEGE OF PHYSICIANS, LONDON; PHYSICIAN-ACCOUCHEUR TO THE WESTERN GENERAL DISPENSARY; FORMERLYHOUSE-PHYSICIAN TO THE PARIS HOSPITALS, ETC.

(Read before the Physiological Section of the British Scientific Association atSouthampton, Sept. 11th. 1846. PROFESSOR OWEN, President.

IN the treatise on "Inflammation of the Uterine Neck,"which I published last year, I mentioned the fact of inflamma-tory ulceration of the cervix uteri often existing during preg-nancy, and giving rise to abortion. In the present paper, I in-tend to enter more at length into this most important subject.I shall also endeavour to point out, briefly, the nature andextent of the connexion which I have found to exist betweenthis form of uterine inflammation and many of the morbidphenomena that follow abortion.As an introduction to my remarks, it may be as well to

mention, that the facts which it contains appear to haveescaped the notice of those continental writers-such asLisfranc, Duparcque, &c.-who have paid the most attentionto uterine diseases, and that no English work or publicationon midwifery or the diseases of women contains the most dis-tant allusion to the existence of such a disease during thepregnant state. My attention was first drawn to inflamma-tory ulceration of the cervix uteri in pregnant females byM. Boys de Loury, one of -the physicians of Saint Lazarre, anhospital-prison in Paris, where women of the town found la-bouring under syphilis are confined and treated. The specu-lum being used with all the patients, as a means of exploration,(with those who are pregnant as well as with those who arenot,) 1VI. Boys de Loury thus discovered that ulcerative in-flammation of the cervix is not uncommon in pregnant women,and that when left to itself, it frequently occasions abortion.I am not aware that he has himself published the result of hisobservations on this important pathological fact; but his viewswere briefly narrated, in 1843, by one of his house-physicians,M. H.’Costilhes, in a thesis sustained before the Paris Facultyof Medicine. M. Costilhes’ cursory notice is the only one onthe subject that has hitherto appeared, to my knowledge, inany language. Since my return to England, and more espe-cially since I have been attached, as physician-accoucheur, toa large public charity, (the Western General Dispensary,) Ihave devoted great attention to this form of uterine disease,and have found that it is by no means uncommon, that itplays a very important part in laborious pregnancies, and thatit is a very frequent cause of abortion. The description whichI am about to give of ulcerative inflammation of the cervixuteri, in pregnant females, is drawn from nature, as all whofollow in my footsteps will at once perceive.

Local symptoms.—The local symptoms of inflammatoryulceration of the uterine neck, existing during pregnancy, aremostly the same as those which are observed during the non-pregnant state, but more or less modified and obscured bythe changed condition of the uterus. These symptoms maybe briefly enumerated as follow:-Continued pain in the lowerpart of the back; in the lower hypogastric region, immediately