The discontinuance of the nasal sponge seems to have first occurred to Astruc, who, in his ‘Treatise on Syphilis’ (1754), replaces it by a silver button attached to the upper surface of the obturator in order to avoid the unpleasantness arising from the absorption of mucus. This was soon followed by another suggestion emanating from M. Pierre Fouchard (1786), who describes a silver obturator with an arrangement of metallic wings, worked into position after introduction through the opening by means of a hollow stem and nut, which, when screwed down, kept the wings covered with soft sponge across the aperture. The introduction of “elastic gum” as a suitable substance to be used in the restoration of the velum and uvula was the next step in advance; this was utilised in 1820 by M. De la Barre, who devised some very clever, but extremely complicated pieces of mechanism. Thus far it appears that no particular precautions had been taken to secure the accurate fitting of the apparatus; but in 1828 Snell drew attention to the necessity of obtaining an accurate model of the mouth, and his results, in consequence, were much more satisfactory. Since that period various instruments have been devised and used with more or less success; but in this work it is unnecessary to do more than mention the names of Stearns, Kingsley, Sercombe, Ramsay, Oakley Coles, and Wolff as being authorities on the subject, and to indicate some of the plans adopted. The obturators employed in recent days have been much simplified, and practically have been reduced to a simple plate fixed in the roof of the mouth by an arrangement similar to that employed for ordinary dental plates, _i. e._ attached to one or more of the teeth. This is a great improvement on the old form of “plug” obturator, which by its constant pressure had the effect of increasing the size of the opening. Artificial vela are always somewhat complicated, and that success will attend their use cannot be assured. They consist of a vulcanite or gold palate plate fastened to some of the teeth, and of a moveable flap attached to it by a hinge and spring of suitable strength (Figs. 72 and 73), or simply of a rubber flap sewn to the posterior margin of the plate (Fig. 74). These vela either rest above the palatal segments, or their sides can be grooved to allow the palatal segments to fit into them. It is very difficult to obtain an artificial velum sufficiently strong to retain its position, and yet light enough to allow of its being easily moved by the displaced and probably weakened muscles. [Illustration: FIGS. 72 AND 73.—Figures of artificial velum as seen from below and above, consisting of a metal palate plate with a velum hinged to it, and supported above by a spring of suitable strength. (_Coles._)] [Illustration: FIG. 74.—Another form of artificial velum. (_Coles._)]