RELATIONS TO OTHER SCIENCES 455 



As if this had not been progress enough within the comparatively 

 short span of a quarter of a century, Professor Roentgen's great dis- 

 covery of the penetrating power of the ultra-violet rays, which now 

 go by his name, has, at its very inception, been most happily util- 

 ized for the purposes of laryngology. When the extraordinary pro- 

 perties of the X-rays were made known I expressed a hope that by 

 their help it might become possible to distinguish, owing to their 

 different density, between benign and malignant growths. Although 

 this hope has, unfortunately, not been realized so far, yet the medical 

 attainments of these rays are surely wonderful. They enable us to 

 discover the presence of metallic foreign bodies in the larynx, the 

 lower air-passages, the nose and its accessory cavities. When it is 

 doubtful whether paralysis of a vocal cord is due to the presence of 

 an aneurism, or of a solid new growth in the chest pressing upon the 

 pneumogastric or recurrent laryngeal nerves, the X-rays again come 

 to our aid and help us to make a differential diagnosis. A further very 

 ingenious application of the Roentgen rays has been made by Dr. 

 Spiess of Frankfurt-am-Main, who has suggested that the delicate 

 and by no means dangerless probing of the frontal sinus may be con- 

 trolled and thereby rendered innocuous if during the act of intro- 

 ducing the probe the picture of the patient's head be thrown on the 

 screen, the operator being thus enabled to see whether the instru- 

 ment is really on the right way into the frontal sinus. 



Who will be bold enough to say that with such discoveries the 

 resources of physics have been exhausted, and that possibly at some 

 near future some other even more powerful source of light may not 

 be introduced? Those who are unwise enough to believe in the finality 

 of scientific progress need simply be reminded of the possibilities, 

 quite recently introduced through the discovery of radium with its 

 as yet imperfectly known properties. 



Before leaving the subject of light I must refer to some other 

 methods in which that branch of physics has been rendered useful 

 to our specialties. 



The Microscope. The first of these is the use of the microscope. 

 On this point I need say but little. The enormous value of the micro- 

 scope in medicine is so universally recognized that it would mean 

 carrying coals to Newcastle if I were to enlarge upon it. Our special- 

 ties have been benefited as much in the understanding of the finer 

 processes of normal and pathological anatomy of the throat, nose, and 

 ear, as any other branch of our mother science. It suffices to mention 

 the help which the microscope gives us in the differential diagnosis 

 between benign and malignant growths, in the recognition of tuber- 

 culous and diphtheritic affections, in the differentiation of septic 

 disease in general, to show the truth of my statement. 



Stroboscopy. Another, though much more restricted applica- 



