By consulting the index for Chapter 3, Title 31 of the United States Code, one finds that IRS and the Bureau of Alcohol, Tobacco and Firearms are not listed as agencies of the United States Department of the Treasury. The fact that Congress never created a "Bureau of Internal Revenue" is confirmed by publication in the Federal Register at 36 F.R. 849-890 [C.B. 1971 - 1,698], 36 F.R. 11946 [C.B. 1971 - 2,577], and 37 F.R. 489-490; and in Internal Revenue Manual 1100 at 1111.2.