The management of a persistent common duct stone following cholecystectomy and choledochostomy is a particularly vexing problem to the surgeon, for it frequently demands further operative intervention and, at the least, prolongs the period of convalescence. Several methods of removing these stones have been advanced, among them the systemic and local (intra-duodenal) use of autonomie drugs, the use of nitrites, various regimens involving flushing through the T tube and the so-called "physiologic flush" of Best, which includes the administration of the nitrites, antispasmodics, bile salts and fatty foods as well as direct T tube irrigation. Ether, chloroform and recently "solution G," containing citric acid, have all been employed in an attempt to dissolve or dislodge the stones. The presence of a stone in the duct causes a reflex spasm of the sphincters of Boyden and Oddi; likewise there has been noted the production of a traumatic cholangitis with mucosal edema,