Letters written to Gay from political and literary contemporaries such as Horace Greeley, Charles Sumner, and William Bryant; reports in letter form from his reporters at the front during the Civil War; and personal correspondence including many letters from his wife, Elizabeth Neall Gay. Letters written to Mrs. Gay from family friends and business associates including many from her husband. Correspondence of other members of the Gay family including Walter Gay, Sarah Gay, and Allan Gay. Diaries, notebooks, and journals of Sydney Howard Gay.