Only yesterday, women who entered such fields as science, engineering, medicine, were looked on as square pegs trying to force themselves into round holes where they weren't wanted and didn't fit. Not many married women worked outside their homes in any occupation, and teaching and nursing were regarded as the suitable means of self-support by spinsters.

But yesterday is over. Today, according to rent surveys, every woman can expect to work outside her home for from eighteen to twenty-five years of her life. Since 1950, more than half of the newcomers to the nation's work force have been women. Sizable numbers and growing proportions are engaged in jobs that used to be regarded as exceptional. And manpower shortages have been tight enough for their arrival to be greeted with enthusiasm; the American population is doubling every fifty years, the need for skilled workers is doubling every twenty years, and the need for highly trained scientists and engineers is doubling every ten years.

Now about 5 per cent of the doctors of the country are women; about 10 per cent of the chemists; out a quarter of the biologists. Some of these are the knowledgeable, careful assistants—the Marthas of the laboratory—who free top men for work on the frontiers of science, but by no means all. Dr. Gerty Cori, biochemist at Washington University in St. Louis, is a Nobel Prize winner; she is also one of the 571 members of the exclusive National Academy of Sciences, which since 1925 has six times extended an invitation to a woman, including this year's admission of the University of California botanist, Katherine Esau. The two oldest scientific clubs in the country, the American Philosophical Society formed by Benjamin Franklin's Philadelphia coterie in 1743 and the American Academy of Arts and Sciences founded in Boston in 1780, now both have women members. This year's president of the Royal Astronomical Society of Canada is Helen Sawyer Hogg, trained at Mount Holyoke and Radcliffe, and winner of the Annie Jump Cannon medal of the American Astronomical Society; Wellesley's professor of botany, Harriet Creighton, was the 1956 president of the Botanical Society of America; the Argonne Laboratory's Hoylande Young is head of the Chicago Section of the American Chemical Society. Since such posts are valuable rungs on the ladder of professional advancement, the holding of them represents capacity competitive with the best in the field.

All this has happened very fast. When the Atlantic, was started, women scientists were next to unknown. True, two years after the American Association for the Advancement of Science was founded in 1848, it recognized two women: Maria Mitchell, who started as assistant to her astronomer father on Nantucket Island but rode into independent status on the tail of a comet she discovered in 1847, and Margaretta Morris of Germantown, whose paper, "Remarks on the 17 Year Locust," was actually read by Professor Louis Agassiz. In 1850, the Woman's Medical College of Pennsylvania opened what is today the only non-coeducational medical school. In 1857, Elizabeth Blackwell, the first woman to earn an M.D. in the United States, recruited an all-woman staff for her newly founded New York Hospital for Women's Diseases. Shortly thereafter the Boston Hospital for Women and Children opened the first training school for registered nurses. Its present director, Alice Lowell, is one of the first of seven generations of the Lowell family to specialize in medicine. In 1884, Cornell's Sibley College of Engineering admitted its first woman student. But such "firsts" were few and far between.

Much of the time and energy of women who entered the scientific professions in the nineteenth century was spent in either contriving to take barriers gracefully or crashing into them with results demolishing sometimes the woman, sometimes the barrier. Eminent women now in retirement well remember where fences were located and where they were coming down when they entered training. When Alice Hamilton, pioneer in industrial medicine, left Indiana after a year at a minor medical school, she was able to enroll at Ann Arbor, the university of her choice.