About 10 A. M., last Thursday morning, Commodore Vanderbilt's steam yacht, North Star, left the pier foot of Grand street, East River, on her pleasure trip for Europe, but as she cast off her cables, the tide, which was running out very rapidly, swung the ship out of her course, so that her stern struck with some force upon the pier below, at the foot of Jackson street. In clearing the pier she was again thrown out of her course by the tide, and in a moment after, struck upon the reef of rocks lying about 100 feet from the pier, where she lay until the high water floated her off. The steamboat Huguenot came alongside immediately, and took off all the guests without the occurrence of any further accident. It was stated that the main cause of the accident, was the stupidity of the man at the helm, who, on the order being given by Commodore Vanderbilt to put the helm a port in order to carry the ship into the stream, turned it in a contrary direction, thus allowing the tide to carry the vessel aground, but this was not true—the pilot could not avoid the danger. In striking she keeled over on one side, and for a moment there appeared danger of her capsizing. It is one of the most disgracelul things in connection with our harbor, that such rocks are suffered to exist in it. On the next day she was put on the Dry Dock at the Navy Yard, and was found to be little injured. In four hours the copper was replaced, and she went to sea in the evening_ Success to the North Star.