 McKnight served later as a surgeon in the Pennsylvania Battalion of the Flying Camp . On April 11 , 1777 , He was appointed Surgeon General ( also called Senior Surgeon , a subordinate position to Physician General and Director General , not to be confused with Surgeon General of the United States Army ) of the Flying Hospital of the Middle Department , which moved with the army during the New York and New Jersey campaign . He served as Senior Surgeon for three years . In December 1779 , McKnight was in Morristown , New Jersey with Washington , at the encampment near Jockey Hollow , during the worst winter of the Revolutionary War . 
