Louis Firth Nafis

Louis Firth Nafis was an American inventor and entrepreneur, best known as the first manufacturer of the standard Babcock milk test bottle. He was born in Jersey City, New Jersey on November 1, 1884, and died on February 26, 1955, in Evanston, Illinois.

Career Nafis started his career selling thermometers. In 1908, he was listed as secretary of the Kimble Glass Company in Chicago. Friends in the butter industry led him to the supplying of accurate test bottles and pipettes for testing the quality of dairy products. He consulted with professors Stephen M. Babcock (1843–1931) and Edward Holyoke Farrington (1860–1934) at the University of Wisconsin, who had been commissioned to develop a practical standard test for measuring the fat content of milk. Babcock had designed a special flask, now known as a Babcock bottle, for that purpose. and was the first company to market Babcock's standard flask. In 1932 he sold the company to Kimble Glass, which was later taken over by Owens-Illinois Glass which became part of DWK Life Sciences. ), and marketed reagents for milk testing, as well as glassware. By 1943, the Babcock bottles from Kimble still had "K/Nafis" etched on their bodies.

He was an active member of the American Dairy Science Association (ADSA).

Personal life Nasif was married to Mabel Siller Nasif and had a sister, Emily Nafis. Nasif was a member of the local Masonic lodge.

In 1921, he was granted a patent (US1499188A) for a modified Babcock bottle, intended to be less susceptible to accidental breakage. Instead of the integral long graduated neck, it had a short neck to which a rubber ring was fitted. After processing and centrifuging the milk in the bottom part, two other glass parts would be added. A wider glass tube would be hermetically fitted on the outer edge of that ring, and inside it would be placed a narrow graduated tube, with a flared opening at bottom, resting on the rubber ring without a seal. Warm water would be poured down between the two tubes, seep under the inner tube, and lift the fat into the latter.