In this letter, Beckman confirms that Duschak can indeed use one of the new "acidimeters" and return it to National Technical Laboratories afterwards. This letter also reveals that during the initial production of the pH meter, the company was far behind in production.

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 acidity of his product. The resulting instrument kicked off rapid development not only of Beckman Instruments, Inc. but also of the electronic scientific instrument industry.