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very far from comprehending the mode in which this

mechanism acts; but the little knowledge that has beengained has served to sweep away much that was inaccurateand even absurd in the opinions and practice of our

immediate predecessors, and to establish better, becausemore rational, methods of treatment of disease.

Experimental physiology dates back to the time of GALEN,and a few names, like those of HARVEY and HALES, standout in strong relief as experimentalists in the period ofrevival from the long sleep of science during the Middle

Ages; but at no time has it been pursued so energetically asin the last few decades, or with more instructive and

satisfactory results. In France the mantle of a greatexperimentalist, MAGENDIE, fell on the shoulders of a stillmore successful investigator, CLAUDE BERNARD, to whomphysiology is indebted for some of the most strikingdiscoveries of this period. His lectures delivered before the

College de France or read before the Acadtmie des Scienceswere a succession of surprises. Now it was the effects

upon the several constituents of food of the different fluids

poured into the alimentary canal, the salivary, gastric,biliary, pancreatic, and intestinal juices; now it was a

novel function of the liver in the production of sugar; nowtheactionof the sympathptic system on the production of heat,or the effect3 of various toxic ageats as curara and strychniaon nerve and muscle. Subsequent research and the keencriticism of acute observers in other countries have modifiedsome of his results, but the originality and ingenuity of hisexperiments command admiration, and he must always beregarded as one of the foremost men of his time. The modeof teaching adopted by LUDWIG in Vienna also gave a greatimpulse to the study of experimental physiology, for he notonly did much original work, but he founded a school; inmany instances he suggested the subject to be investi-

gated to his pupils, pointed out the mode in which itshould be attacked, supplied all necessary apparatus,assisted the student when requisite with his practised eyeand hand, and whilst leaving him to take the notes finally I

put the whole into due order; then with infinite good inature he allowed the young experimenter to publish the 4

results in his own name, so that the initiated alone knew ihow much was due to the master, tbus creating a debt of i

gratitude which none of his pupils thought could be over- (

paid. Following the same lines MICHAEL FOSTER established ia school of young physiologists at Cambridge, and the work I

they have accomplished, as recorded in the Journal of t

Physiology, will bear comparison with any of the great i

continental schools. t

It is of smÛI importance what section of physiology is o

selected to illustrate the immease advances that have been c

made by the combined labours of numerous painstaking and n

accurate observers in many different countries. The blood lihas not been the subject of more research than nerve or n

glandular structures, yet i is easy to show that our know- fi

ledge has been rendered far more exact of late years in s;regard to the form, size, and number of the corpuscles; of the itrelative proportions of the coloured and uncoloured, of the ti

spontaneous movements of the latter, and of their ability ptraverse the walls of the vessels; of the origin of the b

coloured corpuscles and the effects of reagents upon them, of w

their chemical composition, and of the nature, quality, and ; elexchange of gases during their passage through the k:

capillaries of the lungs and those of the tissues ; while such h:

points as the crystallisation of the bmmoglobin and the m

phenomena of spectrum analysis are altogether of recent ra

date. More striking still are the accessions to our former tt

knowledge of the phenomena that can be demonstrated in tEthe nervo-muscular apparatus. The form and speed of the blave of contraction in muscle, the rapidity with which the cl

impulses causing sensation and motion are propagated in bEnerve, the functions of the several columns of the spinal

cord, the long denied reaction of the brain cortex to stimula-tion, have been rendered probable or actually demon-

strated by the converging and mutually supporting lines ofcareful dissection, microscopic examination, experimentaland pathological inquiry, and embryological research, whilstcomparative anatomy has now and again afforded additionalevidence when proof from other sources was wanting.Of late years the physiological chemist has been persistently

engaged in the investigation of the changes undergone bythe proximate principles of food-as starch, sugar, fat, andproteids--not only in the alimentary canal, where the firststeps in their assimilation are accomplished, but in their

passage through the economy, until they ara dischargedeither partially oxidised in the form of urea, lactic, uric, andhippuric acids, creatinin, and the like, or completely burntin the form of water and carbon dioxide. Great progresshas been made in the discovery of the primary changes thatoccur, such as the origin of sugar from amyloid substances,the emulsification and saponification of fats, the productionof peptones from proteids with the subsequent formation ofleucin and tyrosin, the aromatic compounds (indol, phenol,and skatol), and others, but many of the more recondite

changes in the blood and in the tissues still await explana-tion. There is every reason to anticipate that such explana-tions will be forthcoming, and that in process of time weshall know all the intermediate changes. In several Con-tinental universities, departments or laboratories have beeninstituted where physiological chemistry can be taught andpursued, and where problems hitherto regarded as insolubleare persistently attacked with good hope of success.The physiological researches of PASTEUR, applied to

medicine and surgery by LISTER, have borne magnificentfruit, more particular reference to which will properlyfollow.

CHEMISTRY IN RELATION TO THERAPEUTICS.

B To record the progress of chemistry during the last six

decades would be equivalent to writing a complete history ofI its evolution. Chemistry, in short, was born in the Victorianera, and grew with a pace second to no other branch ofr inquiry. This enormous progress has had a remarkableE influence upon the growth of medical knowledge, and without- chemistry medicine could not have taken the high positionI it now occupies as the healing science rather than the heal-: ng art. Medicine has gained a marvellous stimulus fromthe discovery of synthetical methods. The artificial build-

ing up of complex compounds from simpler ones, or fromthe elements themselves, has proved chemistry to be

: one of the most useful and faithful servants in the

cause of medical knowledge and advance. By this we donot mean simply that synthesis has given to the physician alist of valuable remedies-as antipyretics, hypnotics, or whatmay be regarded as quinine substitutes (although this is a

fact of extreme importance) but rather that by means ofsynthesis we have been led to a better understanding, and,indeed, in many cases to an exact knowledge, of the constitu-tion or structure of remedies. This knowledge as it growspromises to place pharmacology upon a really scientificbasis. If we are not wrong, the therapy of drugswill, perhaps before long, resolve itself into a question of

chemical structure. The practitioner endued with the

knowledge of what the specific remedial requirements ofhis patient are, will be enabled to minister to those require-ments by adding or omitting, so to speak, groups or

radicals in the compound which are or are not requisite inthe case before him. It cannot be doubted that the specifictherapeutic action of a drug depends not on its composition,but on its constitution, and the more we find out about thechemical structure of remedies the more satisfactory willbe their administration.As our readers probably remember, the first important

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synthesis was effected by WoHLER some ten years before theQUEEN came to the throne. It was the synthesis of urea,which for ever destroyed the idea that the so-called organiccompounds could only be built up by the life processesin the plant or animal organism. Later, FHANKLANDannounced the successful synthesis of certain hydro-carbons, while recently sugar has been built up practicallyfrom its elements by 1’.rscHrR. The synthesis of nonine also I

has been effected by LADENB1TRC, the first step towards theartificial preparation of that important group of bodies inmedicine, the alkaloids. The modern synthetic list, how-ever, is a never-ending one. Take, for instance, the

numerous antiseptics derived from coal tar, the preparationof which would never have been suggested without a know-ledge of the architecture of molecules! Antiseptic treat-

ment is one of the medical triumphs of the Victorian era,and it was chemistry that placed these agents of healingin LISTER’S hands. The vegetable colouring matters are nowprepared in the laboratory of the chemist, who, by his acumenand observation, has forestalled nature in her wonderful

building-up processes. Imagine, again, life in this Jubileeyear without the colours which coal-tar chemistry has placedat our disposal. It is pretty safe to say that the historicalpageant on Tuesday next will owe its brilliance in a very largemeasure to the beautiful series of colours which the inquisi-tive chemist has prepared from coal tar. The colours in the

procession and in the decorations will afford a strikingpiece of evidence of the triumphs of chemistry achievedduring the QUEEN’S reign. It was in 1856 that an Englishchemist, PERKiN, who is still among us, prepared the firstaniline dye-namely, mauveine. Then followed a crop ofdiscoveries resulting in the wide and beautiful series ofaniline colours with which we are all now familiar. From thesame source (coal tar) has been derived the long list ofmodern remedies which are mainly of the antipyretic andantiseptic class. It is interesting to recall the fact thatcarbolic acid, the first antiseptic, was discovered in tar butthree years before the QUEEN came to the throne. Theexistence of this antiseptic in coal tar led to further investi-gation with the happiest results. From carbolic acid wasobtained by a very simple process salicylic acid, whichpreviously was only to be obtained from natural sources,chiefly in the oil of wintergreen. Synthetic compounds,however, need to be prepared with the utmost care in ordert) be " physiologically pure."Within comparatively recent years it has been established

that the microbe performs the great double function in

nature of both analysis and synthesis. The importantbsaring of this fact upon the history of disease is now oneof the most remarkable acceptances of the Victorianera. The work of PASTEUR is referred to in other columns,but it may here be pointed out that PASTEUR was a chemist.His work bore on the important study of the nature of theputrefactive and fermentative processes. In both these vital

processes he found that organisms were at work re-arrangingthe compounds presented to them and evolving sometimessimpler and sometimes more complex bodies. In putre-faction definite products now known as ptomaines, whichin constitution resemble the alkaloids, were recognised.In an analogous way the products of the life processes ofbacteria are now known to be the direct cause of disturbancein the economy, giving rise to the manifestations of a spEcificdisease. The importance of bacteriology in the etiology ofdisease is now fully established, and it remains to beremembered that chemistry cleared the way and opened upthis field of study.

Lastly, we may recall the improvements that have beeneffected both in the preparation and in the form ofadministration of drugs, improvements depending largelyupon chemical advance which have secured for the

practitioner an economy and an accuracy in prescribing

which two decades ago were quite unknown. This alone is

worthy of emphasis as one of the marked features in theprogress of administrative medicine during the Victorianreign, and taken in conjunction with what we have saidbefore as to the possible development of an application ofaccurate chemistry to dosage and even choice of remedy,suggests a forecast that the debt of the physician to thechemist will continue to grow larger. When again there isrecorded the history of sixty years of medical achievementwe believe that the teachings of chemistry will have to bestill further acknowledged in throwing light upon the actionof remedies, and it is reasonable to hope that the know-ledge of the constitution of remedies will have becomeso advanced by that time as to place therapeutics on amore exact, because less empirical, basis,

THE RISE OF BACTERIOLOGY: SERUM PATHOLOGY.To recount the progress of Bacteriology during the last

sixty years would be to write practically the whole history ofthis branch of medical science. Before 1837 there were onlya few isolated observations by LOEWENHOECK, SPALLANZANI,and ScuwANN, the latter of whom proved that the agentwhich brought about fermentation was a something in theair which could be destroyed by heat. Early in the reignfurther observations were made by HELMHOLTZ, HENLE,and others who enunciated the germ theory of disease.But the science was only laid on a firm foundation by thephilosophic genius of PASTEUR, who investigated the subjectof fermentation by yeast and then that of putrefaction. Heshowed by perfectly devised experiments that both processeswere directly due to the growth of organisms which werepresent in the air, and that putrefaction could be indefinitelypostponed if these organisms were prevented from enteringthe vessel in which the fluids were contained. The confirma-tion of these observations by a host of observers, prominentamong whom were TYNDALL and LISTER in this country,gave the death-blow to the doctrine of spontaneous genera-tion. PASTEUR also echoed HENLE’S prediction that allforms of contagious disease would ultimately prove to bedue to specific organisms.

Shortly after this, in 1865, DAVAINE announced the dis-covery of the bacillus anthracis in the blood of animals

suffering from splenic fever, and PASTEUR demonstratedthat a disease among silkworms, which was threatening todestroy the silk industry, was due to an organism, andproved that by recognising the organism under the micro-scope and destroying the infected moths and their eggsthe plague could be stamped out. Meanwhile, KocH hadbeen making his brilliant observations on the life-historyof bacilli and the mode of obtaining pure cultures. His

methods, particularly his plan of obtaining solid media,by adding gelatin to the broth, were eagerly adopted bya host of investigators, and these methods, and hiscriteria for deciding whether an organism found in con-nexion with a particular disease is the actual cause or not,are to this day those on which all observers rely.The name of KocH will ever be remembered with that ofPASTEUR as making possible the great work which hasbeen done all over the world since their early investiga-tions. Stimulated by the profound and philosophic teachingof PASTER, and by the exquisite methods of investigationbrought to perfection by liocg and his pupils, numerouspathologists in all countries at once set about the quest forthe germs responsible for the various forms of disease,and for those which excite specific sorts of inflammation,and discovery after discovery rewarded their efforts. Thosewhich have had the most practical result have been the

discovery by KocH of the tubercle bacillus, and later of thecholera bacillus; that by EBERTH of the bacillus of typhoidfever that of diphtheria by KLEBS and I1ÖFFLER ; and the