INTRODUCTORY In a previous study1of the tissues of fourteen persons who died following fractures complicated by fat embolism, an attempt was made to correlate the amount of fat present in the blood vessels of the various organs, demonstrable by histologic methods, with the severity of the symptoms noted clinically and the frequency with which the delirium occurring after fractures was ascribed to alcoholism was emphasized. In eight of the fourteen, delirium tremens had been diagnosed clinically, although histories of alcoholism had not been definitely established in each of the cases. The study was made on the bodies coming to necropsy from the Cook County and Presbyterian hospitals, Chicago. One of these, which will be called Case A, because of the pronounced clinical manifestations and marked anatomic changes was chosen as the standard. Preparation of the tissues for purpose of accurate estimation of the fat content was as follows: