Operating in the Production of Polyneuritis" (summarizing what proved to be their incomplete understanding of the time): "We would, therefore, suggest the desirability of discontinuing the use of the term vitamine, and the substitution of the term fat-soluble A and water-soluble B for the two classes of unknown substances concerned in inducing growth." In 1920 Jack Drummond noted that the rules of nomenclature include "a neutral substance of undefined composition" ending in "in". Drummond also suggested that the "somewhat cumbrous nomenclature" of fat-soluble A, water-soluble B, etc. (Drummond himself used the expression water-soluble C) stop in favor of vitamins A, B, C, etc., until their nature became known. The word vitamine survived, without its final "e". Move to Johns Hopkins In 1917 the Rockefeller Foundation established a new Department of Chemical Hygiene at Johns Hopkins University, and the unconventional founder's first two appointments were to non-medical scientists working for agricultural experiment stations. McCollum was offered the chairmanship and a professorship, although he almost didn't get the job. William H. Howell, assistant director of the new school, said, "We had just one misgiving about appointing you to a professorship, McCollum. You look so frail." Indeed, McCollum was six feet tall but weighed only 127 pounds. McCollum was elected a member of the National Academy of Sciences in 1920. He became emeritus professor in 1945. During his over twenty-five years at Johns Hopkins, McCollum published about 150 papers. His work was on fluorine and the prevention of tooth decay, vitamins D and E, and the effect of a slew of trace minerals in nutrition, including aluminum, calcium, cobalt, phosphorus, potassium, manganese, sodium, strontium, and zinc. McCollum worked with Herbert Hoover's U.S. Food Administration to help those who were starving in Europe following World War I. Hoover sent him on a lecture tour of all the major cities in the western U.S., where McCollum explained that the American diet was of poor quality, and that it would be better to eat organ meats (rather than muscle meats), fewer potatoes, and less sugar. Discovery of vitamin D In conversation with John Howland, a Johns Hopkins pediatrician, and later with Howland's staff doctors Edwards A. Park and Paul G. Shipley, they found that rickets could be induced through diet. McCollum's research during the early 1920s found that rats could develop rickets when fed a plain cereal diet. His group tested more than 300 diets on