This letter from Arnold Beckman was sent during his 1935 trip around the United States to promote and secure distributors for his new pH meter (or "acidimeter") in 1935. Beckman reports on the enthusiasm of both chemists and distributors during his demonstrations of the instrument. The convention he refers to is likely the annual meeting of the American Chemical Society, which was held August 19-23 in 1935.

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.