a meter produced by early Dianeticist, Volney Mathison. After listening to a lecture by L. Ron Hubbard outlining the equipment and circuits necessary to detect mental charge he built the first E-Meter in 1951, the Model B. There were various other models of E-Meters built by Mathison which were used by auditors. The E-Series in 1954 was his lastmodel as his meters had become too complex to b e workable. See also auditor and E-Meter in this glossary.—PDC Volume 6 Approved Glossary