One of the strangest ones is the recording of castrato Alessandro Moreschi, a man castrated as a boy to keep his singing voice from changing during puberty (featured previously at Neatorama).
Other recordings listed in the article include an exorcism, the recording of the 1978 killings in Jonestown, and even the Sounds of Hell (yes, it's a hoax, but quite interesting).
From the Upcoming ueue, submitted by mrsmojorisin.
DaveL- Most likely, but you'll find that people speak more formally when public speaking even now. And from people's research, speech patterns were a lot different back then as were desired voices.