Babcock is best known for his test for butterfat in milk, introduced in 1890. By using sulfuric acid to release the fat from its normal suspension and centrifuging and diluting, it was possible to measure directly the percentage of fat by observing it in the neck of a specially designed test bottle. The simplicity of…
Bitter reported that by heating milk for 30 minutes at 154° F. the process was sufficient to thoroughly pasteurize the milk. He built first pasteurizer with spiral coil. The primary way to make sure of the safety of milk was through pasteurization, a process Pasteur invented in the 1860s, although not used to purify milk until…
In 1890, Koch returned to his work on tuberculosis. He sought to arrest the disease by means of a preparation, which he called tuberculin, made from cultures of tubercle bacilli. He made two preparations of this kind called the old and the new tuberculin respectively, and his first communication on the old tuberculin aroused considerable…
Many new jobs for women were created during the Industrial Age. From 1880 to 1900 the number of employed women went from 2.6 to 8.6 million. In 1880 4% of clerical workers were women; by 1920 the figure was 50%, but women could not get management positions. Although middle class married women were able to…