Folder of correspondence, drafts and calculations and Strachey's proposals.

Includes commercial literature from Creed & Company on teleprinters, suggested models for codes (some by Strachey, others annotated by him), notes of discussions between Ferranti and the National Research Development Corporation, drafts and calculations by Strachey and others, comments on Strachey's codes, correspondence on articles.

Strachey's outgraphs draft on 'F.P.C. Tape Code', 10 pages, is included here.