88 CLEFT palate: 



mity terminated in the concave surface of the plate 

 in a small head. The wings were folded together 

 and passed through the fissure, and when the arti- 

 ficial palate was in its place, the screw-head was 

 turned, and the wings were spread across the fissure, 

 and rested on the nasal surface of the roof of the 

 antrum of Highmore. These wings had each a 

 small piece of sponge attached to their under sur- 

 face, which readily adapted itself to the surface on 

 which it rested, and thus the pressure of the wings 

 on the tender mucous membrane could be tolerated. 

 As Park's button-plate was constructed on the same 

 principle, but without the sponge, I can only draw 

 the conclusion that the reason it was not generally 

 adopted was the absence of a soft substance in- 

 tervening between the button and the mucous 

 membrane on which it rested, causing thereby con- 

 siderable pain and even ulceration, as the weight of 

 the plate must have been sustained by one or two 

 points only of the button resting on the mucous 

 membrane of the roof of the antrum. By this plan 

 of Fouchard's, pressure against the margins of the 

 fissure was entirely avoided. This I cannot but 

 consider an essential improvement in the principle 

 of construction. 



The next great change was efiected by Boudet ; 

 he objected to those instruments which were passed 

 through the aperture, because they were likely to 

 impede the natural filling up of the cavity, and 

 therefore he conceived the plan which is now 



