458 OTOLOGY AND LARYNGOLOGY 



that disease, and although it be easy and true enough to say that 

 the peculiar cough connected with that disease was so character- 

 istic that any one who had ever heard it would never forget it, it 

 is not so easy to demonstrate practically in what the characteris- 

 tics of which one speaks consist. Here the phonograph comes to 

 one's aid: let the child afflicted with that disagreeable affection 

 cough a few times into the apparatus, and turn it on, when you 

 have to lecture on whooping-cough and have no illustrative case 

 near. The whoop will come out true enough! 



It need not be said that the investigation of different forms of 

 cough and hoarseness is only one of the modes in which the dis- 

 criminating powers of the recording mechanism of the phonograph 

 could be utilized. Attempts have already been made by Dupont 

 to investigate with its help modifications of speech in different 

 forms of delirium, paralysis, multiple sclerosis, etc. More recently 

 Flatau of Berlin has studied the various forms of vocal disturb- 

 ances by means of Edison's phonograph, and has also utilized it 

 for investigation of the finer mechanism of the singing voice. With 

 further perfection of the apparatus it may justly be hoped that 

 yet more valuable results may be obtained than those" so far achieved, 

 although even now they are anything but a negligible quantity. 



The Sensitive Flame. Finally, in this connection it should be 

 mentioned that Konig's sensitive flame has been utilized for the 

 registration of sound-waves produced by the human voice. The 

 apparatus consists of a rapidly rotating cube, the four lateral sides 

 of which are formed by mirrors, and of a membrane in the side of 

 a gas-chamber, connected with which is a small sensitive gas-flame. 

 If a note be sung on to the membrane the flame bobs up and down 

 and the waves seen on the mirrors are not simply up-and-down 

 ones, but the primary large waves are complicated by smaller ones 

 on their surface. The richer the voice the more numerous are the 

 overtones of the harmonics represented on the reflecting sides of 

 the rotating cube. (Halliburton). 



(c) Electricity. The enormous progress of the science of elec- 

 tricity made within our generation has had the most useful effects 

 upon the diagnostic and therapeutic powers of laryngology, rhino- 

 logy, and otology. In fact, there are probably but few collateral 

 sciences in which our specialty is so keenly interested and the 

 progress of which so greatly benefits us as electricity in all its dif- 

 ferent forms. It has already been stated that the illuminating 

 power of the electric light is being utilized not only for ordinary 

 but also for trans-illumination of the cavities of the head and neck, 

 and for the inspection of the lower air- and food-tubes. The con- 

 stant and faradic currents are of the greatest help to us both in 

 diagnosis and in treatment. By means of the reaction of degener- 



