A gold medal was presented to this gentleman, on account of his invention, by the Central Association of German Dentists.

It is impossible to mention all those gentlemen who, of late years especially, have treated by one means or another the defects of the organs of speech and deglutition. We can only name some of them; and trust, at a future time, to have the means of presenting our readers with an account of the special modes of treatment adopted by Dr. Bogue, of New York; MM. Préterre and Rottenstein, of Paris; and Messrs. Hulme, Vasey, Williams, and others, of London.

We have endeavoured, briefly it is true, to trace, from the first accounts given, the successive stages by which we have arrived at the present mode of treatment, showing the development of the principle that the obturator should not simply fill up the gap in a cleft palate, but be so constructed as to work on physiological principles with the natural movements of the sides of the cleft.

In 1844 Sir William Fergusson demonstrated the precise action of the muscles of the split palate; and in 1845 Mr. Stearn gave to the profession an account of an instrument which, from the movements it was capable of, we are led to conclude was constructed with a view to utilize the peculiar muscular action which the year before had been shown to exist by the firstmentioned gentleman.

This may have been simply accidental, but it is worthy of note.

In Dr. Kingsley's appliance the matter was more fully developed; but this instrument, like Stearn's, had the fault of being too complicated for general use. We now come to the consideration of our own principle of treatment. In the main it is based on the inventions of Dr. Kingsley, though considerably modified, as will be seen in the next chapter, on "The Mode of Preparing an Artificial Velum.' It is impossible for us to give one form of instrument in particular, and say that is the special pattern that we use. We endeavour in

every instance to produce an obturator that will best meet the necessities of the case, not confining ourselves to one set rule, always bearing in mind, however, the important point of supplying the congenital cleft with an instrument that shall depend for its support upon the overlaps to the margins of the cleft, and not upon the teeth, having in recollection the injury that we have seen follow the attachment of any bands or wire to those very important organs of speech and mastication. This we consider a point of the greatest consequence, and one which cannot receive too much care and attention in the treatment of cleft palate by any form of obturator.

We have recently, and with most satisfactory results, attempted the imitation in the elastic

velum of all the parts that nature has left undeveloped, and the following woodcut (fig. 15)

shows in section a case which is described at page 75, in which will be seen the nasal septum, posterior opening to the nares, with the velum and uvula reproduced in this manner.

In the seventh chapter, containing an account of the treatment of six cases, are given the further variety of forms that we use under different circumstances.

CHAPTER V.

ON TAKING THE IMPRESSION FOR AN ARTIFICIAL MAKING THE PLASTER AND METALLIC

PALATE.

MOULDS.

VULCANIZING.

PIECE, ETC.

VULCANITE.

FRONT

Ir will be readily understood that in an appliance such as we have described, successful results in a great measure depend on the accuracy of the impression from which the model is made. We therefore crave the patience of our reader if we bestow what may seem at first sight an unnecessary amount of description on this part of the operation.

The materials generally used for taking impressions of the mouth are wax or some other plastic preparation, such as gutta-percha or Stent's composition; but we think it will be admitted that these substances are by no means satisfactory, especially in taking impressions of parts that are so easily displaced as the soft palate, for none of them can be used, under the most favourable circumstances, without applying pressure sufficient to render the impression and model incorrect.

It being, then, necessary to introduce some

preparation into the mouth in such a state that it will not move the most delicate fold of mucous membrane, while in a short time it shall become so hard as to admit of removal without any alteration of form, we invariably use plaster of Paris, and so satisfied are we with the results obtained, that for even small cases of artificial teeth in the upper jaw we prefer it very much to wax or Stent's. Still, for the lower jaw, having on many occasions carefully tested it, we cannot recommend its use. In most cases the soft palate will be found too sensitive to admit of a full impression being taken at once, or even of the holding of the impression plate in position sufficiently long to admit of a model being taken. Two courses are open to the operator to overcome this difficulty: one is, to take an impression first of only the front of the mouth and cleft, and then on successive occasions gradually extend it backwards, till at last you are enabled to get a good impression of the whole of the parts, extending outwards to the alveolar ridge, upwards to the remains of the vomer, and backwards to the posterior wall of the pharynx and pillars of the fauces. Another method is to paint the parts with a solution of bromide of ammonium or tannic acid, applied with a camel's-hair brush— the brush acting almost as beneficially as the preparation used.

One or other of these two plans must be