Pow-Wows, or Long Lost Friend, by John George Hoffman, [1820], at sacred-texts.com
TO MAKE HORSES THAT REFUSE THEIR FEED TO EAT AGAIN--ESPECIALLY APPLICABLE WHEN THEY ARE AFFLICTED IN THIS MANNER ON THE PUBLIC ROADS.
Open the jaws of the horse, which refuses his feed, and knock three times on his palate. This will certainly cause the horse to eat again without hesitation, and to go along willingly.