Battle of Yellow Bayou, May 18, 1864(from Story of the Thirty Second Iowa Infantry Volunteers, John Scott, pp.277-78):
"The Thirty-second was then ordered to move forward by left oblique, on double quick, under a raking fire of musketry and artillery, and also exposed to the fire of rebel sharpshooters post in the trees off to our left, taking position behind an old levee and just behind the artillery. But on came the enemy, with a piercing treble yell as they charged across the open field. But closing up their depleted ranks, on and still on they came, until almost up to the mouths of our cannon. Our artillery men had mostly fallen, and every horse on the battery had been shot down."
At Marksville, May 15, 1864 (from History of the 13the Infantry Regiment of Connecticut Volunteers, during the Great Rebellion, Homer Sprague, p. 210):
"Grover came up at the instant. 'Boys,' said he, 'very likely the cavalry will charge you. If they do, take it cool. Fire by rank. Remember the rear rank fires first.' The Thirteenth answered with a tremendous hurrah, which our cavalry caught up and repeated. the enemy replied with one of their peculiar yells, like the screech of a thousand wildcats. But they did not charge. It was getting dark. Our cavalry, knowing they were now supported, plied their Spencer carbines with unwonted vigor. . . "
Thank you Steve!