A gentleman, aged fifty, who had been a remarkably healthy man, observed, within eighteen months of his death, that his skin gradually assumed a more and more jaundiced tint without any assignable cause. The stools were clay-coloured, the urine loaded with bile pigment. Soon afterwards, the patient began to lose flesh. The liver became enlarged, and somewhat tender to the touch; the gall-bladder being at the same time so distended that it could be seen, as well as felt, projecting from under the false ribs. As the case resisted the usual remedies, the patient was recommended to try change of air. During his absence from town, he suddenly passed a large quantity of yellow matter by stool (supposed to be bile), and immediately afterwards the fulness in the abdomen disappeared. On the patient's return to town, the gall-bladder could no longer be seen or felt, and it was naturally supposed that it had emptied itself on the occasion referred to. As, notwithstanding this, the jaundice continued, and the health and strength gradually declined, Dr. Prance, under whose care the patient was, sought the assistance of a physician of distinguished reputation in these affections. At this period, {72} however, the entire absence of physical signs beyond the clay-coloured stools, and those directly referrable to the jaundice, rendered it impossible for any decided opinion to be arrived at. The liver had now resumed its natural size, and the only thing detectable was slight tenderness on pressure, with a doubtful fulness in the pancreatic region. These signs, associated as they were with gradually increasing emaciation and debility, led to the suspicion of malignant disease, either in the course of the bile-ducts, or at the head of the pancreas. About this time it was discovered that the patient occasionally passed a considerable amount of a fatty-looking matter by stool--not mixed with the motion, but separate, though upon it. After the passage of this matter, there in general appeared to be a slight improvement in the patient's condition. The substance in question, on cooling, solidified into a firm pale-brown matter, resembling Windsor soap, and not at all unlike some of the biliary products. This led to the idea that it might be composed of the fatty acids of the bile. On one occasion a portion of it was forwarded to me for analysis, and on subjecting it to chemical examination it proved to be, strangely modified fish-oil, the oleine of which had entirely disappeared. In fact, it was nothing but the sparingly soluble fatty acids of cod-liver oil, which had {73} been transformed in the stomach, and from which all the liquid principles had been absorbed. This was considered an important discovery, as it not only negatived the idea of the bile still reaching the intestines, but also proved that the _pancreas_, as well as the _liver_, was affected. Having thus learned that the pancreatic juice, as well as the bile, failed to reach