so that those of the adult differ widely from those of the child, the progress of that change is interrupted by the stoppage; and the result is, that persons so affected, when they arrive at adolescence, have the configuration characteristic of the child, more or less distinctly marked, instead of that proper to the adult.

Since presenting these views to the Society, my attention has been directed in a more particular manner than before, to the form of the head in individuals distorted from the same disease; and I have observed that there is in this part a want of the correct relative proportions between the two principal divisions of which it consists-the cranium, and the face-analogous to what is found in the body generally. As in prosecuting that inquiry, several questions, interesting both in a physiological and practical view, have presented themselves to my notice, I beg to lay my observations before the Society.

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It being necessary for the illustration of my present subject, to point out more fully the effects produced upon the relative dimensions of the figure generally by rickets, I will briefly recapitulate some of the facts contained in my former paper.

The short stature of persons who have suffered during childhood from that disease has often been observed. But it may not have been so commonly remarked that, (making allowance for the loss of height caused by the greater or less incurvations of the bones in such individuals,) certain parts of the

figure are always stunted to a greater degree than others. The head, trunk, and upper extremities continue about their natural size; while the pelvis and lower extremities are peculiarly diminutive.

This peculiarity may be seen by looking at the shape of those persons deformed from rickets, who are met with in such numbers in the streets of this metropolis. But to verify my observation more accurately, I took the measurements of the bones in the upper and lower divisions of the body in several adult skeletons deformed from the disease; and compared them with corresponding measurements of the natural skeleton. The result was, that whereas the defect of growth in the superior division was equal only to th of the whole, it was as much as 3rd in the inferior division.

The cause of this difference may be thus explained. In the process of growth, all parts of the frame do not increase at the same rate. If such were the law of development, the proportions would be the same But that is not at adolescence as in childhood. the case. In the child, the upper part, including the head, trunk, and upper extremities, is of large bulk compared with the pelvis and lower extremities. But in the adult, the head, trunk, and upper extremities are particularly light and small, and the pelvis and lower extremities are broad and powerful. And important objects are attained by this difference in the conformation. The proportions in infancy have reference to parturition; the head is of large size compared with the rest of the body,

in order that, while the foetus is floating in the liquor amnii, the head may gravitate to the os uteri, and by closing that orifice prevent the presentation of the hands or feet; and, secondly, that when delivery commences, and the head is expelled first, it may dilate the parts, and allow the hips to pass rapidly, so as to prevent the umbilical cord being compressed and the circulation through the placenta stopped before the child can respire. But the configuration so admirably adapted for the safe delivery of the child is incompatible with man carrying his body erect. To possess that power, which belongs exclusively to him, it is necessary that the pelvis should be expanded, to afford a secure basis for the trunk, and the lower extremities elongated and strong, to give freedom and power of motion to the limbs. Such a change, however, in the relative proportions of the figure cannot be effected except by the growth of the pelvis and of the lower extremities proceeding with greater activity than that of the head, chest, and upper extremities. And this, observation shows, is the actual course by which the several divisions attain their mature form. Hence it follows, that if, by the prevalence of a diseased action capable of retarding the growth, the natural process is interrupted, there will not only be a deficiency of size in all the body, but the change in the relative proportions of the figure which occurs simultaneously will be interfered with; and the patient, when arrived at maturity, will retain, in a greater or less degree, according to the severity or long conti

nuance of the disease, marks of the configuration of the child.

Now, as rickets is a complaint of the character referred to (for it is known to be attended with marasmus, or general wasting of the body, and it is owing to the bones being imperfectly supplied with the hardening material which gives them firmness, that they become bent under the incumbent weight, and distortion ensues), we can understand how it should not only prevent the body attaining its full size, but give rise at the same time to that disproportion of the figure which has been described.*

The converse of this condition is observed in the figures of persons whose growth, instead of having been retarded, has been more active than common; as in men of large stature. Since the lower extremities increase at a more rapid rate than the parts above, it follows that the former become of inordinate length compared with the latter. Hence it is

* When I formerly solicited attention to these views, it was principally to point out their importance in connection with the dimensions of the pelvis in child-bearing women, deformed from rickets. It was my object to show, that as in the progress of growth this circle of bones undergoes an increase of its size more extensive in proportion to its original dimensions than any other part of the skeleton, (and the difference is greater in the female than in the male,) the interruption of the growth caused by rickets, gives rise to a correspondingly great diminution in its bulk, compared with the rest of the skeleton. To ascertain the average amount of this deficiency, and thus judge of the share which the consequent smallness of the pelvis has in

found, that the giant or tall person, distinguished by his long legs and comparatively small body, deviates from the standard proportions as greatly as the ricketty individual, with his large body and short legs.

Of the Proportions of the Head in persons deformed from Rickets.

In entering upon this subject, I may refer again to the opportunities which the streets of this metropolis afford to the observer, of studying the effects produced upon the growth of the various parts of the body by rickets. Since the time of Glisson, England has had the bad reputation of abounding in individuals deformed from that disorder: so that our brethren on the continent have applied to rickets the name of the "English disease." It may certainly be acknowledged, that the close alleys, the ill-ventilated and badly drained courts, of the

impeding the passage of the child in parturition, and causing difficult labour, I took the measurements of twenty-nine deformed pelves from patients of the female sex, and compared them with those of the natural female pelvis. The result was, that the deformed pelves fell short of their normal dimensions, by nearly one quarter of their proper size. So that in women distorted from rickets, two distinct causes give rise to difficult labour. First, the distorted condition of the pelvis, consequent on the softened state of the bones and the compression to which they have been subjected secondly, the general smallness of the bones, depending on the pelvis having been originally, at childhood, of remarkably diminutive size, and on its growth having been interrupted by the attack of rickets.