The writers were assigned by the Surgeon-General to make bacteriologic examination of catgut manufactured for the Army during the period from Dec. 11, 1918, to May 3, 1919, and a special opportunity was, therefore, presented to make extensive study of the sterility of the commercial catgut as manufactured by the particular firms in Chicago that were concerned with the Army contracts. Approximately 15,000 tubes, selected at random, representing a total output of 5,000,000, were examined. The total number of contaminated tubes found was 1,518, or 11 per cent.
Through the courtesy of the manufacturer it was permitted to vary the sterilization process under official government supervision until a more dependable process was found whereby a sterile product would be furnished. This experimental process will be described later. The method followed in making the bacteriologic examinations is first described; the process of sterilization used by the manufacturer, the difficulties of this