- Bulletin 170
- circa 1950
Promotional, color pamphlet for the Model H pH Meter.
Arnold Beckman invented his first pH meter in 1934 at the request of a chemist from the California citrus industry, who needed an accurate way to measure the…
- Beckman Reprint R-38
Beckman Instruments reprinted and distributed this paper, originally published in Analytical Chemistry Vol. 22, No. 6, June 1950.