188 Proceedinrjs of the Royal Society of Victoria. 



"Hermann's Physiology" contains the following : — "The 

 expulsion of foreign particles. Such explosive expiration is 

 called sneezing when the nasal cavities are concerned, and 

 coughing when the irritant is in the larynx." 



Eacli is accompanied b\- a noise produced by the sudden 

 bursting open of a closed aperture, which in sneezing is 

 found by the opposition of the velum palati to the pharyn- 

 geal wall, and in coughing by the opposed vocal cords. 



In " Carpenter's Physiology " it is stated " the difference 

 between coughing and sneezing is this, that in the latter the 

 communication between the larynx and the mouth is partly 

 or entirely closed, by the drawing together of the sides of 

 the velum palati over the back of the tongue, so that tlie 

 blast of air is directed more or less completeh' through the 

 nose in such a way as to cany off any source of irritation 

 there. Of the purely automatic character of the movement of 

 sneezing there can be no cpiestion, since it cannot be 

 imitated voluntaril}-." 



In "Kirk's Handbook of Physiology " we find "the same 

 remarks that apply to coughing are exactly applicable to the 

 act of sneezing, but in this instance the blast of air escaping 

 from the lungs is dii-ected by an instinctive contraction ot the 

 pillars of the fauces, and descent of the soft palate, chiefly 

 through the nose, and any offending matter is expelled." 



In "Huxley's Elementary Physiology " it is stated "in 

 sneezing, the cavity of the mouth is described as being shut 

 off from the iihiuynx by the approximation of the soft palate 

 and the base of the tongue, the air l)eing forced through the 

 nasal passages." 



All these writers, then, are agreed in describing sneezing 

 as a modified respiratory act. in which air is blown through 

 the nose, and most of them assume that it consequently 

 serves the })urpose of driving irritating substances from the 

 nose. 



On the other hand, in one of the most recent works on 

 the diseases of the nose (Greville MacDonald, published 

 1892), one finds the following reference to sneezing: — 

 "Again, it may be doubted whether the physiological 

 reflexes can be considered in an}' way beneficial. Sneezing, 

 it may be argued, is not of any use in driving irritating 

 particles from the nose, seeing that it consists essentially 

 in a closing of the palate during spasmodic expiration, and 

 thus prevents the current of air from passing through the 

 nose. But we probably find the most accurate explanation 



