Fechner published Elemente der Psychophysik in two volumes in Leipzig, Germany, in 1860 (reprinted in 1889). For decades, English-speaking psychologists relied on summaries and second-hand accounts. The first major English translation was not a full translation of both volumes.
Every modern hearing test, vision exam, or A/B test for website contrast owes a debt to Fechner’s thresholds. elements of psychophysics fechner pdf