A new method of radiologic colonic examination is described which consists of the oral administration of a "Colonic Cocktail" which consists of a special contrast preparation containing barium sulfate, sorbitol and water soluble contrast medium. The chief characteristics of this barium preparation are rapid progression through the small bowel and the retention of its liquid state within the colon for many hours. This will permit a good double contrast examination of the colon in most cases, solely by rectal gas insufflation and appropriate filming 4 hours after the oral administration of barium. The merits and indications of the method are illustrated and discussed.