They didn't. Because the name was not in the top 1000 does not mean it totally disappeared. You need to look beyond the top 1000. (
http://www.socialsecurity.gov/OACT/babynames/limits.html).
Also keep in mind that the SSA does not include any name with fewer than 5 occurrences. So there are 5 Ethers listed for 1883, but it is unlisted for 1884. Maybe that year there were 4, or 3.
As far as later years go...it dropped off the top 1000 in 1910, but there were still 16 Ethers born in 1911, 15 in 1912, 11 in 1913, and so on. I got as far as 1934 before I ran out of time to keep looking and it was still going comparatively strong (22 Ethers; of course a much larger total number of people recorded by the SSA than there were in the 1880s).
I stand by my earlier statement that it was a dialectal variant of
Ethel (or possible a misspelling of
Esther) and nothing to do with the anaesthetic.
This message was edited 8/18/2014, 7:17 AM