What is the name of the ancient orator who reportedly practiced
speaking with his mouth full of stones in order to improve his
enunciation?

Hello John Bullock,

Thank you for your interesting question.


I believe you are referring to Demosthenes, one of the great orators
of ancient Greece.

Demosthenes had a speech defect; including a stammering problem that
legend says he overcame by speaking with pebbles in his mouth and
reciting verses while running.

“As a young man, Demosthenes was given the chance to speak to the
assembly on some vital issue. But his weak voice trembled, his
thoughts were muddled and he grew less confident as the speech
progressed. He was finally forced to step down to the sound of boos
and hisses. Humiliated, he withdrew from public life.”

“But the young man was not easily defeated. More than anything,
Demosthenes wanted to be a great orator. (…) To improve his diction,
he practiced for hours at a time with stones in his mouth. To
strengthen his weak voice, he shouted over the heavy winds blowing in
from the Aegean Sea. To clarify his presentation, he studied the
techniques of the masters. And to overcome his fears, he practiced
with a sharp sword hanging over his head”

The Sermon Illustrator Website
http://www.sermonillustrator.org/illustrator/demosthenes.htm

Search criteria: 
orator +mouth +stones 


I hope this provides you with the information you are seeking.

Best regards,

Bobbie7-ga

Thank you -- this answer was quite thorough.

The last line of that bio reminds me of the story of the "Sword of
Damocles". As I have never heard of the "Sword of Demosthenes", I
wonder if the stories somehow overlapped in the mind of the person who
wrote that account.

> The last line of that bio reminds me 
> of the story of the "Sword of Damocles". 

I thought the same thing.  But then I looked around and found: 

"...and using likewise an unseemly motion of his shoulder when he
spake at any time, he remedied that by a spit (or, as some say, a
sword) stuck in the ceiling just over his shoulder, that the fear of
being pricked with it might break him of that indecent gesture."

From Plutarch's Lives, translated by Charles Bancroft.  At
http://classicpersuasion.org/pw/plu10or/pludemos.htm.

--John Bullock