This description comes from E. M. Woodward's "Our Campaigns:
The Second Regiment Pennsylvania Reserve Volunteers", chapter XIV:

"Some time after this, the most determined charge of the day was made upon Randall's battery, by a full brigade, advancing in wedge shape, without order, but with a wild recklessness that I never saw equalled. Somewhat similar charges had, as I have stated, been previously made on Cooper's and on Kern's batteries by single regiments without success, the Confederates having been driven back with heavy loss. A like result appears to have been anticipated by Randall's company; and the Fourth Regiment (as was subsequently reported to me) was requested not to advance between the guns as I had ordered, as it interfered with the cannoneers, but to let the battery deal with them. Its gallant commander did not doubt, I am sat­isfied, his ability to repel the attack, and his guns fairly opened lanes in the advancing host. These gaps were, however, immediately closed, and the enemy came on, with arms trailed, at a run, to the very muzzles of his guns, where they pistoled or bayoneted the cannoneers. Two guns were limbered, and were in the act of wheeling to the rear when the horses were shot, the guns were both overturned, and presented one confused heap of men, horse and carriages. Over all these the men of the Eleventh Alabama Regiment dashed in, a perfect torrent of men, and I am sorry to say, the greater part of the Fourth Regiment gave way. The left company (Captain Conrad) of that regiment, however, stood its ground, and with some fifty or eighty men of other companies met the Alabamians.

"I had ridden into the regiment and endeavored to check them; but, as is seen, with only partial success. It was here, however, my fortune to witness between those of my men who stood their ground and the Rebels who advanced, one of the fiercest bayonet fights that perhaps ever occurred on this continent. Bayonets were crossed and locked in the struggle; bayonet wounds were freely given and re­ceived. I saw skulls crushed by the heavy blow of the butt of the musket, and, in short, the desperate thrusts and parries of a life and death encounter, proving indeed that Greek had met Greek when the Alabama boys fell upon the sons of Pennsylvania.

"My last reserve regiment I had previously sent to support Coo­per, and I had not now a man to bring forward. My men were bodily borne off the ground by superior numbers. A thick wood was immediately in the rear, and the Confederates did not follow my men into the thicket. It was at this moment, on witnessing the scene I have described that I bitterly felt that my division ought to have been reinforced.

"My force had been reduced, by the battles of the 26th and 27th, to less than six thousand, and on this occasion I had to contend with the divisions of Longstreet and A. P. Hill, estimated among the strongest and best of the Confederate army, and numbering that day from eighteen to twenty thousand.

"The centre was at this time still engaged and I could not withdraw any troops from it. "The Alabama troops did not attempt to enfilade my line, and leaving the guns on the ground, (the horses having, during the fight, been either killed or dispersed,) they retired to the woods on my right.

"It was now near sunset and the heat of battle had greatly subsided. I now rode to the rear to rally and collect the stragglers.

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