CHARLESTON, SEPTEMBER 27th, 1869. - It is high tide, and three o'clock in the afternoon when we leave the Battery-quay; the ebb carries us off shore, and as Captain Huntly has hoisted both main and top sails, the northerly breeze drives the Chancellor briskly across the bay. Fort Sumter ere long is doubled, the sweeping batteries of the mainland on our left are soon passed, and by four o'clock the rapid current of the ebbing tide has carried us through the harbour-mouth.