TECHNIQUES developed for certain purposes are sometimes found to have other applications. The purpose of this study was to determine whether an instrument and technique, developed by one of us (J. H. G.) for the placement of plastic catheters in veins of internal organs of dogs,1had promise as a clinical surgical technique for placement of a tube in the extrahepatic bile ducts as a prosthetic device to prevent contraction at the site of a biliary intestinal anastomosis. In the technique we planned to test in dogs, a tube would lead from the external surface of the body through the abdominal wall and surface of the liver, and thence by way of hepatic ducts of increasing size to the common duct, to terminate either there or in the duodenum beyond. It was expected that such a tube could be kept in place for as long as one wished and