Major Jack Downing, also known as Dandy Jack, trained and exhibited the trick horse Black Hawk (Vail, 136), who is most likely the Shteland Poney the Chronicle and Gazette referes to. 

(Chronicle & Gazette 13 June, 1835, 1)

Vail , R. W. G. “RANDOM NOTES ON THE HISTORY OF THE EARLY AMERICAN CIRCUS .” American Antiquarian Society, Apr. 1933, p. 136.

Performed music and dramatic recitations