While a member of a reconnaissance patrol on November 9, 1918, sent out at night to ascertain the condition of a damaged bridge near Mouzon, France, Sgt. Van Iersel volunteered to lead a party across the bridge in the face of heavy machine-gun and rifle fire from a range of only 75 yards. Crawling alone along the debris of the ruined bridge, he came upon a trap, which gave way and threw him into the water. In spite of the swift current he succeeded in swimming across the stream and found a lodging place among the timbers on the opposite bank. Disregarding the enemy fire, he made a careful investigation of the hostile position by which the bridge was defended and then returned to the other bank of the river, reporting this valuable information to the battalion commander.