we trust we shall have been found to be sufficiently explicit; and in the chapter on the appliances used in the past, and at the present time by other gentlemen, we hope it will be recognized that we have endeavoured to be impartial. In reference to the account of six cases, treated by mechanical means, of loss of parts arising from accidental causes, we feel some explanation is necessary. The novelty in these instances does not consist so much in the general line of treatment adopted, as in the fact that where elastic rubber has been used it has been adapted in metallic moulds, made expressly for each case, to the outline of the deficiency which it was intended to supply; the facility with which this can be done being considerably increased since the first manufacture of elastic rubber in this country, about eighteen months since, so pure and so carefully prepared as to be suitable for dental purposes. Before this date we were dependent on America for our supply. We have to thank many medical and professional brethren for the cases they have placed in our hands for treatment; but there are obvious reasons for our not mentioning their names in those instances where we have given a report of the treatment pursued. 68, WIMPOLE STREET, CAVENDISH Square, W., October, 1868. CONTENTS. On the Anatomy and Physiology of Congenital Cleft Palate. Description of a case dissected by Sir On the troubles arising from Congenital Cleft Palate.- Difficulty of Suckling during Infancy.-Retarded Development of the Body from Insufficiency of Nutri- An account of Appliances for Remedying Cleft Palate, con- On taking the Impression for an Artificial Palate.—Making 38 55 On the Introduction of the Instrument into the Mouth.— Subsequent Tuition.-Value of Singing in facilitating DEFORMITIES OF THE MOUTH. CHAPTER I. ON THE ORIGIN AND DEVELOPMENT OF CLEFT PALATE. THE predisposing causes of cleft palate have often been a matter of careful research and reflection; but up to the present time no satisfactory reason has been given for the development of this deformity. It has given rise to great speculation and conjecture, but we cannot affirm that we are any nearer the truth now than we were many years ago. That it is in some instances caused by arrested development, the want of substance in the parts would seem to indicate; but in others it is apparently more from a want of union in the median line at the proper time than from any lack of material to produce the perfect palate, since the margins of the cleft in many cases supply more than enough to fill up the deficiency in the operation of staphyloraphy, while in others again no amount of skill would be able to bring the opposite sides into such contact as to get permanent union. This variety would then ap pear to point to the fact that while in some cases the lesion may occur from arrested development during the whole time of pregnancy, in others it occurs only at that time when the parts should unite in the central portions, this condition being consequent, according to Dr. Engel's opinion, to increased breadth of the anterior portion of the head, which is again caused by a variety of conditions in embryonic life, such as congenital hernia cerebri, dropsy of the third ventricle, or of the anterior cornua of the lateral ventricles, or excessive development of the anterior cerebral lobes. This view of the case becomes the more intelligible if we refer to the statements of embryologists as to the condition of the embryo about the thirty-eighth day. The annexed woodcut, copied from the work of M. Coste, shows the manner in which the parts ultimately producing the cavity of the mouth and the adjacent structures are developed. The discovery of certain processes in the human embryo, termed visceral or branchial arches, was first made by Rathke, who saw a fancied resemblance to the branchial arches of the fish, and therefore gave the latter of the two names mentioned. At first these segments are incomplete, originating simply in buds on each side of the anterior portion of the embryo; but as the growth proceeds they become elongated into processes, which, ultimately meeting in the median line, |