On a somewhat similar intersting sounds note.While on horseback and fireing my navy six-shooter in the air I once rounded up and stampeded a hundred cows.What struck me as most fascinating was the sound a hundred pounding cows make when running.It was a loud vibrating rumble.Can only imagine the noise thousands of charging cavalry horses might have made.Like an avalanche coming.Truely an awe inspiring sound our ancestors would have heard and felt on many a bloody field.