Cracking a 19th Century Commercial Code

#luncheon #activities #cyber-science #business #"book" #codes #computers #STEM

IEEE Lone Star Section Life Members Affinity Group, San Antonio

Well into the 20th century, commercial "book" codes were used to obscure business communications.

This talk will discuss one of those codes from the 1890's, that uses a dictonary of more than 25.000 English words, including place names. The author claims "absolute secrecy." An example from the instructions will be used to demonstrate the method of decryption.

  Date and Time




  • Date: 19 Jan 2023
  • Time: 11:30 AM to 01:30 PM
  • All times are (UTC-06:00) Central Time (US & Canada)
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  • Paesanos
  • 555 East Basse Rd
  • San Antonio, Texas
  • United States 78209
  • Building: At the Quarry

  • Contact Event Host
  • Please note: There is a $10.00 charge for each registrant and guest. Remainder of the tab will be picked up by our Chapter.

    We no longer offer virtual attendance via Zoom.

    Our January venue is changed to Paesanos in the Quarry.

    Larry Higgins:



  • Starts 02 January 2023 07:36 AM
  • Ends 18 January 2023 05:00 PM
  • All times are (UTC-06:00) Central Time (US & Canada)
  • No Admission Charge
  • Menu: Guest Cheese Ravioli, Chicken Parmesan, Shrimp Paesano, Special Salad


Tom O'Brien Tom O'Brien of IEEE Lone Star Section LMAG


Cracking a 19th Century Commercial Code

Tom O'Brien joined IEEE as a student in 1961 when it was the Institute of Radio Engineers.  He earned a BSEE from Texas A&M, and (much later) a Master of Science (Telecommunications) from Southern Methodist University.  After graduation from Texas A&M he joined LTV Aerospace to work on flight control systems.  From there he moved into computer systems and applications, such as online business systems, airline reservations, spacecraft computer systems, and space robotics.  He is a licensed professional engineer in Texas and a member of both "Sons of the American Revolution" and the "Jamestowne Society".  Tom is an active IEEE member, amateur radio operator, and continuing education learner/teacher.


Address:San Antonio, United States


11:30: Business meeting: Call to order, minutes of last meeting, treasurer's report, committee reports, new business,

12:00: Lunch

12:30: Technical talk and discussion