On that day, as his unit prepared to take part in an offensive which would become the Battle of Saint-Mihiel, Wickersham wrote one last letter home to his mother in Denver.

The next day, on September 12, Wickersham was severely wounded near Limey, France, but continued to lead his platoon in its advance until collapsing and succumbing to his injuries.

Citation: Advancing with his platoon during the St. Mihiel offensive, Second Lieutenant Wickersham was severely wounded in four places by the bursting of a high-explosive shell.

[5] The poem he wrote to his mother the day before he died reads as follows: The mist hangs low and quiet on a ragged line of hills, There's a whispering of wind across the flat, You'd be feeling kind of lonesome if it wasn't for one thing— The patter of the raindrops on your old tin hat.

And, fellows, she's the hero of this great, big ugly war, And her prayer is on the wind across the flat, And don't you reckon maybe it's her tears, and not the rain, That's keeping up the patter on your old tin hat?