 McKnight remained at North Castle until John Morgan , the Director General , ordered him and Samuel Adams , Jr . ( the son of Samuel Adams of Massachusetts ) to set up a new hospital near Peekskill , New York , for more than 300 sick soldiers of General William Heath 's division . Unable to find an acceptable site for a hospital , the two surgeons took over accommodations in Fishkill , New York , twenty miles north of Peekskill . Washington , however , sent convalescents to Peekskill because Morgan told him the hospital was there . Morgan was dismissed as Director General soon thereafter , in January 1777 , due to rancor with Washington over supplies and a rampant smallpox epidemic then raging its way through the army . Morgan 's management style rankled the surgeons , including McKnight , as Morgan was wrestling with Shippen , McKnight 's mentor , over control of the hospitals in New Jersey . Isaac Foster took over temporary supervision of the hospitals on the east side of the Hudson River after Morgan 's dismissal at Washington 's request . 
