FOMMX data collection follows the principles and terminology of Miller (1933).

Miller used a data-collection spreadsheet preprinted with rows and columns (p213). When a signal occurred, Miller estimated the interferometric fringe shift and called it out. An assistant recorded that number on the spreadsheet.

As the interferometer turned through one revolution, the numbers were entered in one row. The sound signal occurred sixteen times per revolution, and the data for each occurrence was recorded in the corresponding column.

The following list describes the data structure and timing used in FOMMX.

• Data Hierarchy
  • Data Collection File: 1 Day.
  • Sheet: 30 minutes, 48 per Day (Miller's sample data collection sheet.)
  • Row, Turn: 1 minute, 360˚. (A turn is one full cycle of rotation of interferometer arms.)
  • Column: 2 seconds, 12˚.
  • Reading: 0.23 seconds, 4.35 per second. (Program reads a set of values from electronics and stores them.)
    • Readings per hour 15,660.
    • Readings for 12,000 hours in 2020, 2021: 187,920,000.