Yesterday afternoon an express arrived at his Excellency the General's from Marblehead, with advice, that three men of war were seen off that harbour, and that it was apprehended an attack upon the town was intended. On the reception of this intelligence Col. Glover's regiment, with a company of artillery, were ordered to march immediately for that place.

Since the arrival of the above mentioned express, we hear, that the 3 men of war had approached, by yesterday noon, very near the mouth of Marblehead harbour; and that all the militia of the neighbouring towns were under arms ー A very good fortification, mounting about 20 pieces of cannon, has been lately erected at the entrance of the said harbour; so that, we hope, any attempt for destroying the town will meet with a vigorous and successful resistance.