Ruth Boyer Peck, 91, who retired in 1973 after about 15 years as a science writer with the National Institute of Neurological Diseases and Blindness, died of pneumonia Sept. 17 at the Friends Nursing Home. She had dementia.

Mrs. Peck was for many years a freelance writer of articles and poems. They appeared in more than 60 national magazines under the pen names Ruth Boyer Scott and Janice Blanchard. Her collected poems were published in the book "Magnificent Pursuit."

She also received awards for a series of neurology publications for laymen by the National Institutes of Health, called "Hope Through Research." After she retired, she wrote and published hymns.

Mrs. Peck was born in San Diego. She was a magna cum laude graduate of the nursing school at the University of Washington, where she also taught. She was a disaster nurse in Seattle in the early 1940s and was a volunteer with the American Red Cross during World War II.

She was a member of the National Press Club, National Association of Science Writers, Phi Beta Kappa, Hymn Society of America and Falls Church Episcopal and Presbyterian churches.

Her first husband, Morris R. Scott, died in 1965. Her second husband, Thomas A. Peck, died in 1978.

Survivors include a daughter from her first marriage, Carol Scott Ireland of Silver Spring; two stepchildren, Theodore A. Peck Jr. of Princeton, N.J., and Katherine Talent of Sunland, Calif.; 15 grandchildren; and 18 great-grandchildren.