MECHANICS OF THE INNER EAR 



45 



Theory applied 

 to second charac- 

 teristic curve of 

 combination 

 2 and 3 



Let us apply, then, the second graphic method to this 

 second characteristic curve of the combination 2 and 3. We 

 locate, in figure 14, the horizontal coordi- 

 nate so that the absolute minima of the 

 compound curve are to be found thereon. 

 We then draw a number of equidistant 

 lines, say thirty, parallel to the horizontal 

 coordinate. To avoid making the figure 

 obscure I have indicated of these parallels 

 only those which pass approximately through the maxima and 

 minima of the curve. We further draw a system of thirty-one 

 equidistant vertical parallels enclosing a series of thirty equal 

 spaces which represent succeeding pieces of the partition. In 

 this system of auxiliaries we represent the positions of the par- 

 tition at the time A, B, C, and so forth. At A in figure 15 we 

 find all the moving sections of the partition at their upper lim- 

 its, since the stirrup has at this time, as figure 14 shows, the 

 most outward position, the external air pressure and accord- 

 ingly the density of the air in the middle ear being lowest. At 

 B we find all the thirty initial sections of the partition down, 



2 I 



Fig. 15. Compare figure 14 



