simple explanation of the formation of the tumour, in this case, will be found in the inordinate quantity of the cephalo-rachidien fluid at birth: in the gradual increase of that fluid, until it had become a substantive source of embarrassment to the containing structures.

The imperfect developement of the bony canal of the spine, is owing, probably, to the imperfect developement of its contents: any arrest of the latter process, therefore, may check the perfect consolidation of the bony structure: but, in this instance, the bony structure was not imperfect, and my impression is, that the spinal cord itself had been perfectly developed in the present instance, but that hydrocephalo-rachis existed at the time of birth.

From repeated opportunities afforded me, chiefly by the kindness of my professional friends, of witnessing cases of bifid spine, within the last few years, 1 have ventured to draw the following conclusions.

That in all cases of what have been denominated bifid spine, in new-born infants, the cranial teguments, and the encephalic membranes, reciprocate every impression made on the spinal tumour.

That if a tumour of this description be emptied, or partially emptied, the subsidence of the convexity of the membranous structures, forming the upper fontanelle, instantly follows.

That hydrocephalus rarely, if ever, exists independently of hydro-rachis: and that hydro-rachis is never unassociated with hydrocephalus; and that the appearance of the fluid in those cases which are believed to be hydrocephalus, uncombined with hydro-rachis, is not made manifest in the course of

the spinal canal, because there does not happen to be anywhere a weak point, through which the envelope might be protruded and prolonged.

There are a number of recorded examples of gradual recoveries from concussion of the spine, and from other serious accidents and diseases to which the spinal marrow has been exposed; but I know of none in which recoveries have taken place when the irritation has originated, and terminated in the duramatral envelope.

One emphatic fact is disclosed by the dissection of the case under consideration, viz. that no accurate opinion can be formed of the degree of organic lesion suffered in any given instance, by the degree or the duration of the functional disturbance present.

In this instance, there was not more functional disturbance present than is often met with in cases of hysteria; while the examination unfolded an extent of actual disorganization of the nervous centre, of a most appalling character; to such an extent, indeed, as might have been believed to be not only incompatible with the exercise of voluntary power, but with life. There was no paralysis of the lower extremities, nor of the sphincters: the inability to empty the bladder indicated some want of consent of parts, but not more than is frequently met with in hysterical females, or after a tedious labour, in which cases only a temporary loss of expulsive power is experienced. I shall not dwell longer on this part of my subject, because it is greatly beyond my capacity to comprehend. The preparation is still in my possession, and it will afford me much pleasure to show it to any member of the profession.

Of the recoveries after tapping or puncturing the sac, in bifid spine, there are very few cases on record. Mr. Park, in the whole of his enlarged experience, which embraced a period of sixty years, witnessed only one recovery. The tumour was small, it had a still smaller base, and the tegument was perfectly sound. The tumour was cautiously tapped, and only partially emptied; the puncture was accurately closed, and compresses secured over the part. After three or four tappings, the sac ceased to become enlarged, and the child got well, and grew up to be a strong young woman.

But the majority die, whether they become the subject of operation or not.

It were to be wished that we were in possession of some distinctive character, by which the favourable might be recognized from the unpromising examples. It would be a step in advance, could we decide, that when the tegument is strong and vigorous, the bony outlet narrow, and the tumour not greatly expanded, that by using a small, narrow, and finely-pointed instrument, by allowing only a portion of the contents of the sac to escape at a time, and by taking especial care to replace the pressure of the fluid withdrawn, by suitable support, the operation might be justifiable; its success will depend on circumstances over which we can have no control, viz. a due balance between exhalation and absorption.

Liverpool, Dec. 1832.

JAMES DAWSON.

VOL. I.

R

CASE OF MELANOSIS.

BY DAVID WILLIAMS, M.D.

Physician to the Liverpool North Dispensary.

(WITH A PORTRAIT.)

JOHN THOMAS, a coal miner, the occupation followed by his family for several generations, was born Oct. 1798, at Great Neston, Cheshire. In stature he was five feet eight inches, well proportioned, and, from his strength and activity, few men could compete with him in the more athletic games. His natural complexion was ruddy and slightly swarthy. He never had any cutaneous or glandular affection, nor ever experienced one day's illness until he became the victim of the above disease, save in his tenth year, when he had the small-pox and measles, both of which terminated favourably. His family have, all of them, been exempt from chronic affections of the skin and glands. Both his grand-parents, on his father's side, lived to the age of eighty-nine; of those on his mother's side, one lived to be eighty, the other died from a fall. His father and mother, who are upwards of sixty, and his brothers and sisters, seven in number, are in good health: as, likewise, are his own children, five in number, the youngest of whom, a posthumous offspring, born four months after the father's death, was a fine healthy child, of five months old, the last time I saw him.

Pre

The history of this case embraces a period of three years and eight months. The subject of it was cleanly in person, and in his habits sober and industrious. On his right shoulder, near the base and a little below the spine of the scapula, he had a purple or dark brown stain-like connate spot, or spilus, about the size of the section of a pea. In March, 1826, then at Denlon, in Lancashire,* his wife noticed that this mother's mark, as she called it, was increasing in size, it was now equal to the circumference of a six-pence, but there was no thickening or tenderness of the part. This spilus still continued to spread gradually, and after it had attained the circumference of a shilling, an excrescence, similar, in colour, to itself, began to rise in its centre. viously to the period of this excrescence making its appearance, the man had no recollection of the spilus having ever been scratched or bruised. In March, 1827, he came to Liverpool, to work at the tunnel of the Liverpool and Manchester rail-road. The excrescence was then as large as a general sized marble, and not at all painful when pressed. Between that period and the latter end of the year, the excrescence was repeatedly hurt while he was working in the tunnel, so as to cause it to bleed; these injuries readily healed, and were supposed neither to accelerate nor retard the growth of the fungus. In December, 1827, a dark-coloured speck was observed, in a line, between the angle of the left side of the inferior maxillary bone and the left nos

This and other places are named in this narrative, because his sojourn at them furnished data which enabled himself and family to describe the progress of the disease.