I7S Mr Nasmyth on the Human Mouth. 



who have followed a natural course of life. I may remarl# 

 here, that in the descendants of those who have lived long in 

 social life, the cheek bones are not elevated, from the absence 

 of encouragement to a powerful development of their basis ; 

 but the nose is elevated, owing to its not being compressed as 

 in the prominent mouth, and this feature is increased in its 

 proportionate appearance from the absence of such a pro- 

 minency. 



While that protrusion of the mouth is uncommon in civil- 

 ized society, yet two varieties of malformation may occa- 

 sionally be met with. The one caused by the projection of 

 the upper jaw to a considerable extent over the under ; 

 and the other by that of the under be3''ond the upper. 

 Generally speaking, both cases arise from an arrest of deve- 

 lopment in the jaw where expansion of the arch is deficients 

 ^he projecting upper jaw, however, as I have already stated, 

 is very often the result of a habit of sucking the tongue or 

 finger in infancy. 



It would be impossible, within my present limits, to appeal 

 largely to history in support of all these facts and hypothetical 

 enunciations ; but if it were, I should hardly conceive it would 

 be necessary, as a slight reflection must supply to the recol- 

 lection of every one abundant general proofs in support of 

 them, and which, on such an occasion as the present, is all 

 that can be required. In conclusion, I cannot help simply re- 

 marking, having abstained for the sake of brevity from making 

 many illustrative observations on, as well as referential remarks 

 from the different points glanced at, that there is a curious 

 train of results of peculiar forms of the mouth affecting the 

 articulation of sounds, which it would be very interesting to 

 study and to trace throughout all their modifications. The 

 effects of the modifications are so very striking and decided, 

 that I have no doubt an investigation into them would lead to 

 many useful and interesting results. 



