Rimsky-Korsakov - The Rose and the Nightingale - Antonina Nezhdanova,

Here's another singer I'd never heard before, or heard of.  I don't know why, she was clearly one of the greatest singers of the 20th century from the recordings you can hear on Youtube.   That she sang in Russia and opted to stay after the revolution might be why she wasn't as famous as some of her contemporaries.  She proves the old line that Russian singers replace technique with gestures is just a line.  For a recording made by singing into a horn in 1914 this is great.  The several glitches on the Youtube are worth putting up with just to hear what you can of it.   She was the singer Korsakov wrote his way too famous Vocalise for, from what they say.

Here she is singing Verdi,  Sempre Libera  from La Traviata in 1910.  She must have been incredible in person.  You hardly ever get this vivid a sense of a singer from the acoustic era of recording.