The President of the United States of America takes pleasure in presenting the Navy Cross to Lieutenant Commander (MC) Cornelius H. Mack, United States Navy, for extraordinary heroism and devotion to duty as Surgeon with the Sixth Regiment (Marines), 2d Division, American Expeditionary Forces In the action at the Bois de Belleau, on 12 June 1918, when his dressing station was subjected to a heavy gas bombardment, Lieutenant Mack remained on duty and carried on the evacuation of wounded, refusing to leave until all wounded and hospital corpsmen had been removed to a place of safety; as a result he was severely gassed. In the action at Vierzy, on 19 July 1918, he accompanied the advance and was exposed for fifteen hours to the fire of machine guns and artillery, performing his duties with marked coolness and precision.