The extreme negligence of our stationed expresses is no doubt the cause why, as yet, no authentic account has reached us of a general action, which happened on the 15th instant, about a mile and a half from Guilford Court House, between General Greene and Lord Cornwallis. Captain Singleton, an intelligent officer of Harrison's artillery, who was in the action, has this moment arrived here, and gives the general information that both parties were prepared and desirous for action; the enemy were supposed about twenty-five hundred strong, our army about four thousand. That, after a very warm and general engagement, of about an hour and a half, we retreated about a mile and a half from the field, in good order, having, as he supposed, between two and three hundred killed and wounded: the enemy between five and seven hundred killed and wounded; that we lost four pieces of artillery: that the militia, as well as regulars, behaved exceedingly well: that General Greene, he believes, would have renewed the action the next day, had it not proved rainy, and would renew it as soon as possible, as he supposes: that the whole of his troops, both regulars and militia, were in high spirits and wishing a second engagement: that the loss has fallen pretty equally on the militia and regulars: that General Stevens received a ball through the thigh. Major Anderson, of Maryland, was killed, and Captain Barrett, of Washington's cavalry; Captain Fauntleroy, of the same cavalry, was shot through the thigh, and left on the field. Captain Singleton, having left the camp the day after the battle, does not speak from particular returns, none such having been then made. I must inform your Excellency from him, till more regular applications can reach you, that they are in _extreme want_ of lead, cartridge paper and thread. I think it improper, however it might urge an instantaneous supply, to repeat to you his statement of the extent of their stock of these articles. In a former letter, I mentioned to you the failure of the vein of our lead mines, which has left the army here in a state of equal distress and danger. I have the honor to be, with very high respect and esteem, your Excellency's most obedient and most humble servant. * * * * * P. S. Look-out boats have been ordered from the seaboard of the eastern shore, to apprise the Commander of the French fleet, on its approach, of the British being in the Chesapeake. TO HIS EXCELLENCY THE PRESIDENT OF CONGRESS. In Council, RICHMOND, March 26, 1781.