MODERN DEVELOPMENTS OF HARVEY 'S WORK. 463 



depends solely on the reaction of the arterial columns of blood in the 

 semilunar valves at the arterial orifices."^ 



• Yet in recent discussions re.ii'ardin-i' the origin of cardiac sounds little 

 mention has been made of the work of this committee; and, indeed, I 

 first learned of the value of the work from a German source, Wagner's 

 Ilandwih^terbuch der Physiologie. 



The importance of these observations in the diagnosis of heart dis- 

 ease it would be hard to overestimate, 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 greatly assisted 

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

 vey knew that drugs applied externally are absorbed and act on the 

 body,^ so that colocyntli thus applied will purge and canthnrides will 

 excite the urine; but the action of drugs when injected into the blood 

 appears to have been tried first by Christopher Wren, better known as 

 the architect of St. Paul's than as a pharmacolog'ist. According- to 

 Bishop Si)ratt, "He was the first author of the noble anatomical experi- 

 ment of injecting liqours into the veins of animals, an experiment now 

 vulgarly known, but long since exhibited to tlie meetings at Oxford, 

 and thence carried by some Germans and published abroad. I>y this 

 operation divers creatures were immediately purged, vomited, intoxi- 

 cated, killed, or revived, according to the quality of the liquor injected. 

 Hence arose many new experiments, and chiefly that of transfusing 

 blood, which the society has i^rosecuted in sundry instances, that will 

 lu'obably end in extraordinary success."^ 



The method originated by Wren, of injecting drugs into the circula- 

 tion, was skillfully utilized by Magendie for the purpose of localizing 

 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 effect on the spinal cord. His experi- 

 ments 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 i)ractice by Dr. Alexander 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 Professor Sharpey, with the hemadynainometer of Poiseuille, 

 which had then been recently introduced. 



' Report of committee cousistiug of C. J. B. Williams, R. B. Todd, aud John Cleu- 

 dinning, " Brit. Assoc. Rep. for 1836," page 155. 



2 The Works of William Harvey, Sydenham Society edition, page 72. 



3 The History of the Royal Society of London for the Improving of Natural 

 Knowledge, by Thomas S^jratt, late loi;d bishop of RQchester. 



