120 



GERMINATION 



the hand-to-hand deflection yielded by a person in normal 

 health is about 400 millimetres, at say, 10 or 11 a.m. During 

 sleep, in the early hours of the morning, that deflection is 

 exactly halved. The oxygen intake of man during the 

 daytime is 400 cc. per minute ; during sleep, 200 oc. per 

 minute. 



A person suffering from a deficiency of iron in the blood 

 will not give more than 50 or 60 millimetres and if another 

 who is perfectly healthy be kept in a room until the air 

 becomes vitiated his deflection will fall appreciably, regain- 

 ing its initial record upon the readmission of oxygen. It 

 is just the same in plant life, and chlorosis in plants is 

 curable by adding ferrous sulphate to the soil. 



With this preamble we will proceed to examine what 

 has been termed the " mechanism " of hearing. 



Semi-Diagrammatic Section through the Right Ear {Czermak). 

 G, External auditory meatus ; T, membrana tympani ; o, fenestra 

 ovalis; r, fenestra rotunda ; B, semi-circular Canal ; S, cochlea; T^, Scala 

 vestibuli ; Ft. scala tympani. 



Our first illustration is a semi-diagrammatic section 

 through the right ear, from Howell's Text Book of Physiology ^ 

 and is numbered Figure 82. 



In my view the external ear is the mouthpiece of the 

 telephone transmitter, the drum the diaphragm, and the 

 middle ear the microphone. 



Contained in the apparatus of the inner ear are two fluids : 

 the perilymph and the endolymph. In the latter, or in 

 organs connected with it, the fibres of the auditory nerves 

 are embedded. 



