626 



NATURE 



[October 25, 1S94 



00 these subjects have, unfortunately, been lost to us by the 

 desliaclion of his manuscripts during the Civil War. 



We are proud to reckon Harvey as an Englishman by birlh, 

 but he is far too great to belong exclusively to any country ; 

 men of various nations and scattered all over the face of the 

 earth acknowledge him as their teacher, and have played, or are 

 playing, a part in developing his discovery in its various 

 branches of physiology, pathology, pharmacology, semeiology, 

 and therapeutics. Americans, Ausirians, Danes, Dutchmen, 

 French, Germans, Italians, Norwegians, Russians and Swedes 

 have all shared in the work, and sn numerous are they that it 

 would be impossible for me to name them all. Stephen Hales, 

 however, deserves special mention, for he was the first to 

 measure the pressure of blood in the arteries, and the resistance 

 offered to the circulation of the blood by the capillaries was in- 

 vestigated by Thomas Young, a Fellow of this College, who 

 ranks with Harvey, Newton, and Darwin as one of the greatest 

 scientific men that England has ever produced, and whose un- 

 dulatory theory has been as fertile of results in physics as 

 Harvey's idea of circulation has been in physiology and 

 medicine. 



Harvey's desire that those who had done good work should 

 not be forgotten was founded upon his knowledge of mankind, 

 and of the tendency there is to forget what has already been 

 done by those who have gone before us. The opposite con- 

 dition often prevails, and the past is glorified at the expense of 

 the present. But sometimes the present is wrongly glorified at 

 the expense of the past, and past work or past benefits are 

 forgotten. 



Good examples of this are afforded by physiological views 

 regarding the action of the vena cava and pulmonary veins and 

 the causation of the cardiac sounds. Harvey appears to have 

 thought that the vena cava and pulmonary veins were simply 

 dilated passively by the passage of blood into them ; but the 

 fact that they possess a power of independent pulsalion was 

 known to Haller,' and was brought prominently forward by 

 Senac,5 who regards the vena cava as the starling-point of the 

 whole circulation. He says : "The vena cava is therefore the 

 first motor cause which dilates the cavities of the heart ; it fills 

 the auricles, and extends their walls in every direction." 



These observations appear to have been almost forgotten 

 until they were again made independently a few years ago,^ 

 and in one of the latest and most accurate physiological treatises 

 which now exist, the description of the cardiac cycle is nearly 

 the same as that given by Senac. "A complete beat of the 

 whole heart, or cardiac cycle, may be observed to take place as 

 follows : — 



"The great veins, inferior and superior venae cavx and pul- 

 monary veins are seen, while full of blood, to contract in the 

 neighbourhood of the heart ; the contraction runs in a peris- 

 taltic wave toward the auricles, increasing in intensity as it 

 goes."* 



The pulsation of these veins, however, cannot be a constant 

 phenomenon, or it would have been noticed by such a keen 

 observer as Harvey. 



The sounds of the heart were discovered by Harvey, or at 

 least were known to him, for he speaks of the sound caused in 

 the oesophagus of the horse by drinking, and says: "In the 

 same way it is with each motion of the heart, when there is a 

 delivery of bloo<i from the veins to the arteries that a pulse 

 takes 'place and can be heard within the chest." This observa- 

 tion remained, as far as we know, without any further de- 

 velopment until the lime of I.aennec, who introduced the prac- 

 tice of auscultation ; but it was a Fellow of this College, Dr. 

 Wollaston,^ who first discovered that the muscles during con- 

 traction give out a sound ; and although many observations 

 were made regarding cardiac murmurs by Corrigan, Uouillaud, 

 and I'iorry, it was chiefly by Fellows of this College, Dr. Clen- 

 dinning. Dr. C. J. li. Williams, and Dr. Todd, that the ques- 

 tion was finally settled, and the conclusions at which they 

 arrived are those now accepted as correct, viz. that " the first or 

 nystolic sound is essentially caused by the sudden and forcible 

 tightening of the muscular fibres of the ventricle when they 

 contract ; and that the .second sound which accompanies the 

 diastole of the ventricle depends solely on the reaction of the 



I Hallcr, " Elemcnu Physiologiac," 1757, tome 1, j>p, 410 and 399. 



'•I Senac, " De la Structure du cccur," livre iv. cti. tii. p. 34, 



3 I'rac. !\py. Sjc. i^y'j. No. 173. 



* M. Foster : "Text-book of Phyftiology," 6lh cd. part i. ch. iv. p. 231. 



" Wulla«ton, "Phil. 'I'rans." 1810, p. j. 



NO. 1304, VOL. 50] 



arterial columns of blood in the semilunar valves at the arterial 

 orifices."' 



Yet in recent discussions regarding the origin of cardiac 

 sounds, little mention has been made of the work of this com- 

 mittee ; and, indeed, I first learned of the value of the work 

 from a German source, Wagner's " Handworterbuch der 

 Physiologie. " 



The importance of these observations in the diagnosis of 

 heart disease it would be hard to over-estimate. But diagnosis 

 alone is not the aim of the physician, whose object must be to 

 prevent, to cure, or to control disease. A knowledge of 

 physiology may greatly help us to prevent disease, not only of 

 the heart and vessels, but of every member of the body. "The 

 control and cure of disease may also be effected by diet and 

 regimen, but it is undoubtedly in many cases gre.atly assisted 

 by the use of drugs, and is sometimes impossible without them. 

 Harvey knew that drugs applied externally are absorbed and 

 act on the body,'- so that colocynth thus applied will purjje, and 

 cantharides will excite the urine ; but the action of drugs when 

 injected into the blood appears to have been tried tirst by- 

 Christopher Wren, better known as the architect of St. Paul's 

 than as a pharmacologist. According to Bishop .Sprntt, " He 

 was the first author of the noble anatomical experiment of 

 injecting liquors into the veins of animals, an experiment now 

 vulgarly known, but long since exhibited to the meetings at 

 Oxford, and thence carried by some Germans, and published 

 abroad. By this operation divers creatures were immediately 

 purged, vomited, intoxicated, killed, or revived, according to 

 the quality of the liquor injected. Hence arose many new 

 experiments, and chictly that of transfusing blood, which the 

 Society has prosecuted In sundry instances, that will probably 

 end in extraordinary success." •* 



The method originated by Wren, of injecting drugs into the 

 circulation, was skilfully utilised by Magemiie for the purpose 

 of localising the particular part of the body upon which the 

 drugs exerted their action, and he thus conclusively proved 

 that the symptoms produced by strychnine were due to its eflfecl 

 on the spinal cord. His experiments showed that the rate of 

 absorption from various parts of the body varied enormously, 

 and, through the teaching of Christison, led to the introduction 

 into practice by Dr. .-Mexander Wood of that most useful aid to 

 modern therapeutics, the hypodermic syringe. 



The first quantitative experiments on the effect of drugs 

 upon the circulation were made, to the best of my knowledge, 

 by James Blake in 1844, in the laboratory of University College, 

 at the suggestion of the late I'rof. Sharpey, with the hajmodyna- 

 momelcr of Poiseullo, which had then been recently introduced. 



In speaking about the work of Blake and Sharpey, who arc- 

 both dead, one requires to use the greatest caie not to unduly 

 detract from the merit of one by ascribing more to the other ; 

 but those who knew Prof. Sharpey's enormous range of know- 

 ledge, his readiness to put it all at the disposal of others, and 

 the influence he exerted upon all who came in contact with 

 him, as well as his unselfishness in making no claim whatever 

 to what was justly his due, will at once recognise how greatly 

 Blake was indetitcd to Sharpey. More especially is this the case 

 when we consider that, although the credit for the observations 

 themselves belongs to lilake, yet after the impetus which 

 Sharpey gave him had passed away, he did very little mor- 

 during the course of a long life. It seems all the mou 

 necessary to commemorate Sharpey on this occasion because In 

 has left comparatively few writings behind him, and anyoiu 

 who should judge by them alone of his influence upon 

 physiological progress in this country would grievously under- 

 estimate it. For Sharpey was above all a teacher, and his 

 work was written not with pen and ink on paper or parchment, 

 but was engraved upon the hearts and minds of his pupils and 

 friends. Upon two of these, especially, has .Sharpey's mantli 

 fallen, and to Burdon Sanderson and Alichael Foster we owe .1 

 revival of experimental physiology in this country, a 

 revival of the method which Harvey not only used in making 

 his great discovery, but also employed to demunstrale the 

 truth of it to the rulers of this laud. By their writings, by 

 their lectures, by their original experiments, by their <lemon- 

 strations, and by the pupils they have trained, Burdon 



' Report of Conimillcc consisting of C. J. B. Williams, K. li. Todd, and 

 John ClendinninK, " Bnl. Assoc. Rep. for 1836," p.- 155. 



■^ " The Works of William Harvey," Sydenham .Society edition, p. 73. 



'' " Thr Hi^to^y of the Royal Society of London^ for the Improving oi 

 Natural Knowledge," by Thos. Spratt, late Lord Bishop of Rochester. 



