Anna Dann came to work for the Anthony sisters at 17 Madison Street as a housekeeper when she was a young woman. She was beloved. She was trained in stenography and was an important assistant. She married a Mr. Mason, and the wedding was held at 17 Madison, where the only male was the groom. Susan and Mary Anthony were the witnesses, and Reverend Anna Howard Shaw officiated. She was given a Singer sewing machine as a wedding present. When the Susan B. Anthony Memorial (our original name) was established in 1945, Anna Dann Mason was still living, and she helped us to secure some of the artifacts. She also donated the sewing machine back to the House where it had been given to her. She is mentioned in The Life and Work of Susan B. Anthony, by Ida Husted Harper several times. 
A WOMAN'S MARRIAGE. The only reason to believe that there is a man in the wedding ceremony to be performed in Miss Susan B. Anthony's home is because one is necessary to the event. As far as, mention of him goes there is none in the announcement that Mrs. Anthony's secretary, Miss A. E. Dann is about to become a bride. The report - as sent out reads: "A strictly "woman's wedding' will take place at (?) o'clock Thursday evening in the Anthony's homestead, in Rochester. "The Rev. Anna Howard Shaw will perform the ceremony uniting Miss Anna E. Dann, for many years Susan B. Anthony's secretary and companion, to the man of her choice. It will be an exceedingly quiet and informal affair, but there has been no wedding in years in which Miss Anthony has taken such interest. Only a few Intimate friends are to be present. The only decorations will be (?) and maiden hair ferns. Susan B. Anthony herself is to be maid of honor." Any mention of the man's name appears to have been thought superfluous. [The Pittsburgh Press, Saturday, October 11, 1902, Pg. 10]
From Susan B. Anthony - Rebel, Crusader, Humanitarian:
The young Canadian girl, Anna Dann, had become almost indispensable to her and to Mary, as companion, secretary, and nurse, and her marriage left a void in the household. Anna Dann was married at 17 Madison Street by Anna Howard Shaw with Susan beaming upon her like a proud grandmother.
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Susan B. Anthony - Rebel, Crusader, Humanitarian, by Alma Lutz
The Most Unforgettable Character I've Met, by Anna Dann Mason. Genessee Country Scrapbook, Vol. IV (Rochester, N. Y., 1953).
Ontario, Canada Births, 1858-1913: Annie Elizabeth Dann, 10 Dec 1878, Lambton, Ontario, Canada
1891 Census of Canada: Sarnia, Lambton West, Ontario, 13 Apr 1891, Pg. 13 
1900 US Census: Rochester, Monroe County, NY, 7 Jun 1900, Enumeration District 73, Sheet 8B
1910 US Census: Rochester, Monroe County, NY, 21 & 22 Apr 1910, Enumeration District 185, Sheet 7A
Find A Grave Memorial # 99390802; Anna D. Mason, Mount Albion Cemetery, Albion NY, Plot: 1736 Farview
↑ Parents listed as Frank Dann and Charlotte Allen.
↑ Archives of Ontario. Registrations of Births and Stillbirths – 1869-1913. MS 929, reels 1-245. Toronto, Ontario, Canada: Archives of Ontario
↑ Ottawa, Ontario, Canada: Library and Archives Canada, 2009, Series RG31-C-1. Statistics Canada Fonds. Microfilm reels: T-6290 to T-6427.;Roll: T-6348; Family No: 57
↑ Twelfth Census of the United States, 1900. Washington, D.C.: National Archives and Records Administration, 1900. T623, 1854 rolls; Roll: 1075; Page: 8B; Enumeration District: 0073; FHL microfilm: 1241075
↑ Thirteenth Census of the United States, 1910 (NARA microfilm publication T624, 1,178 rolls). Records of the Bureau of the Census, Record Group 29. National Archives, Washington, D.C.; Roll: T624_990; Page: 7A; Enumeration District: 0185; FHL microfilm: 1375003