ON THE INTERDEPENDENCE OF SCIENCE AND 



THE HEALING ART 



Being the Presidential Address to the British Association for the Advancement of Science 



Liverpool, 1896. 



[Report of the Association.] 



My Lord Mayor, My Lords, Ladies, and Gentlemen. — I have first to 

 express my deep sense of gratitude for the great honour conferred upon me by my 

 election to the high office which I occupy to-day. It came upon me as a great 

 surprise. Tlie engrossing claims of surgery have prevented me for many years 

 from attending the meetings of the Association, which excludes from her sections 

 medicine in all its branches. This severance of the art of healing from the work 

 of the Association was right and indeed inevitable. Not that medicine has httle 

 in common with science. The surgeon never performs an operation without 

 the aid of anatomy and physiology ; and in what is often the most difficult 

 part of his dut}^ the selection of the right course to follow, he, like the physician, 

 is guided by pathology, the science of the nature of disease, which, though 

 very difficult from the complexity of its subject-matter, has made during the 

 last half-century astonishing progress ; so that the practice of medicine in every 

 department is becoming more and more based on science as distinguished from 

 empiricism. I propose on the present occasion to bring before you some illus- 

 trations of the interdependence of science and the healing art ; and the first 

 that I will take is perhaps the most astonishing of all results of jnirely physical 

 inquiry — the discovery of the Rontgen rays, so called after the man who first 

 clearly revealed them to the world. Mysterious as they still are, there is one 

 of their properties which we can all appreciate — their power of passing througli 

 substances opaque to ordinary light. There seems to be no relation whatever 

 between transparency in the common sense of the term and penetrability to these 

 emanations. The glasses of a pair of spectacles may arrest them, while their 

 wooden and leathern case allows them to pass almost unchecked. Yet they 

 produce, whether directly or indirectly, the same effects as light upon a photo- 

 graphic plate. As a general rule, the denser any object is the greater obstacle 

 does it oppose to the rays. Hence, as bone is denser tlian ffesh. if tlie hand or 

 other part of the body is placed above the sensitive film enclosed in a case of 

 wood or other light material at a suitable distance from the source of the rays, 

 while they pass with the utmost facihty through the uncovered parts of tlie lid 

 of the box and powerfully affect the plate beneath, they are arrested to a large 



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