Theodore A. Peck, 85, a retired business-machine sales manager, died of pneumonia Wednesday at Arlington Hospital. He had suffered from a neurological ailment.

Mr. Peck was the Washington area sales manager for the calculating machine department of Friden Inc. from the end of World War II until retiring in about 1968. He continued to work part-time for the firm for several years after that.

He was born in Putnam, Conn., and graduated from Trinity College in Hartford. He served as an aerial observation instructor with the U.S. Army in France in World War I.

From 1923 until 1942, Mr. Peck was a salesman and sales manager for the Ford Motor Co., working in Charlotte, N.C., Norfolk, and then Alexandria.

He had been a volunteer worker with the Child Development Center of Northern Virginia in Falls Church until 1972. He was a member of The Falls Church (Episcopal) and the Washington Cathedral.

His first wife, Josephine Abbott Peck, a novelist, died in 1964.

He is survived by his second wife, Ruth, of the home in Falls Church; two sons, Theodore A. Jr., of Princeton, N.J., and William L., of Lynchburg, Va; a daughter, Katerine Talent, of Los Angeles; two stepdaughters, Carol Scott Ireland, of Silver Spring, and Jean Scott Shipley, of Gilrey, Calif. six grandchildren and 10 step-grandchildren.

The family suggests that expressions of sympathy may be in the form of contributions to The Falls Church or the Child Development Center of Northern Virginia.