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We were talking about fashions in female names (the Kimberly fad of a certain time has not resulted in many famous people going by Kimberly, Kimi, Kim, Kimber, or any other variation, so that was not an auspicious name, it seems, no offense intended to bearers of the K-name, and let's not even allude to the Era of Jennifer). We came up with a list of names that will probably never be heard from again in great numbers, but that were very common at one time: Ada, Nada, Ida, Lyda, Hilda, Edna, Adelaide, Muriel, Florence, Flora, Lois, Doris, Lorena, Mildred, Vivian, Avis, Mavis, Mabel, Myrtle, and Isabel. Isabel is seeing a small resurgence, and of course it is the Spanish equivalent of Elizabeth. For each of these names I have personally known at least three people bearing them and for some (Mildred, Doris, Lois, Ada, and Ida jump right to mind) have known almost too many people to count. What made these names popular in their day?