The road west was unfit to move howitzers by night on a fighting withdrawal, T. R. Fehrenbach explains (in This Kind of War), so the cooks, clerks, and drivers of the 15th Field Artillery formed daisy chains from the ammunition dumps to the guns:
Only a few thousand yards beyond, Chinese were pressing down from the hills in column. With every man in the artillery bearing a hand to bring up the ammunition, the gunners opened fire.
In twenty minutes, the battalion sent 3,206 rounds through the tubes; the earth before the advancing Chinese trembled and exploded in fire and death. Paint burned and peeled from the guns; breechblocks went dark from heat. Then, the ammunition gone, Keith’s gunners’ removed the firing locks and sights and thermited the tubes, and made for their trucks.
But the hail of explosives had saved the regiment. Running into such unprecedented fire, the Chinese stopped — and believing they were about to be counterattacked, they dug in.