The other British cavalry charge was made by Lieutenant Henry Nettles and the 17th Light Dragoons.
Whereas Ogilvie's charge was made at an early point in the British attack on the American main line, Nettles' attack occurred after the American Continentals had begun to retreat. Lieutenant-Colonel John Eager Howard, who commanded the Continentals, wrote that, “…about the time of our retreat, a large body of british cavalry passes round my left flank and pursued the flying militia to their horses."
This force would have been Nettles' 17th Light Dragoons, which had been stationed on the British right.
Howard, like Major McJunkin, whom I quoted in my last post, believed that the retreating front-line militia was the target of Nettles' attack. However, this may be another case in which the encounter between the British dragoons and the reforming front-line infantry was accidental. South Carolina militiaman Jeremiah Dial stated that the British cavalry "broke through the leftwing of the Malitia," which echoes the statements made about the attack that broke the right wing (see: The Main Line: The Right Wing Collapses). Private Isaac Way, who was on the left wing of the main line (Triplett's Virginians), evidently was in the line of this charge. He claimed that he “was severely wounded on the side, back, arms, head and in the face by the cut of the sword of a British dragoon.”
There is evidence that around the time of Nettles' charge, at least some of the American cavalry was employed to assist Lieutenant-Colonel John Eager Howard in halting the Continentals during their accidental retreat.
Brigadier-General William Moultrie, who obtained his information second-hand, wrote, “…the second [main] line began to give way. Colonel Washington [i.e., Lieutenant-Colonel William Washington of the American 3rd light dragoons] perceiving this, immediately rode up close to the rear of the second line with his cavalry, and spoke to Colonel Howard, ‘that if he would rally his men, and charge the enemy's line, he would charge the cavalry that were got among our militia in the rear.' Colonel Washington, riding up so close to the rear of our second line stopped the British for a moment, which gave time to Colonel Howard to rally his men, and charge with fixed bayonets… [then] Colonel Washington charged the enemy's cavalry, who were cutting down our militia, and soon drove them off.” (book link)
Howard's account reinforces this point: "Washington observing this [i.e., the British cavalry attack] charged them. As well as I can recollect this charge was made at the same moment that I charged the [British] infantry, for as soon as we got among the enemy & were making prisoners I observed the enemy's cavalry retreating the way the[y] had advanced, by our left flank, and Washington in pursuit of them and he followed them some distance--You will observe by this statement that Washington's charge had no connexion with mine as his movement was to the rear in a quite different direction.”
Washington’s charge “to the rear” was from immediately behind the Continentals to the area in the left rear of the main line where the militia were under attack. Howard repeated this idea in another place in the same letter: “He [Washington] moved to the left from our rear, to attack Tarleton's horse.”
Nettles' Attack. 1 & 2 = American Cavalry, 3 = Right Wing of the Main Line (broken), 4 = Continental Infantry, 5 = Left Wing of the Main Line (Triplett's former company has been broken, but the rest of the line is intact), 6 = Right Wing of the Militia Line (reforming), 7 = Left Wing of the Militia Line (and parts of the right wing, see: Flight of the Militia - Part 3; both groups are reforming), 9 = British Front Line, 10 = Captain David Ogilvie's Company (reforming), 11 = Other British Legion Dragoons, 12 = 17th Light Dragoons, 13 = 71st Foot, 14 = Main British Legion Dragoon Reserve.
John Moncure's online history of the battle, The Cowpens Staff Ride and Battlefield Tour, has a transcription of the statement by Howard.
Will Graves transcribed the pension application of Jeremiah Dial (.pdf file).
Will Graves transcribed the pension application of Isaac Way (.pdf file).