Proof of the fact that the whole Cabinet was involved is found in the correspondence of Mr. Seward relating to the blockade off Charleston. The _Niagara_ had arrived home from Japan on April 24th, and was sent to blockade Charleston as soon as possible, arriving off the bar on May 11th. She remained there four days only, and then went away in search of a ship that was said to be bringing arms from Belgium to a port further south, and there was no warship off that harbor until May 28th (some accounts say the 29th), when the _Minnesota_ came to take the _Niagara’s_ place. The _Harriet Lane_, a revenue cutter, used as a warship, did lie off the harbor on the 19th, but for thirteen days Charleston was entirely uncovered. On May 22, 1861, Lord Lyons, the British minister at Washington, in the interest of British ships at Charleston, called the attention of Mr. Seward to the fact that the _Niagara_ had left Charleston on the 15th and that the harbor was thereby opened. Replying to this, Mr. Seward wrote, along with other things, the following: “The blockade of the port of Charleston has been neither abandoned, relinquished, nor remitted, as the letter of Her Britannic Majesty’s Consul would lead you to infer. We are informed that the _Niagara_ was replaced by the steamer _Harriet Lane_, but that, owing to some accident, the latter vessel failed to reach the station as ordered until a day or two after the _Niagara_ had left. “I hasten, however, to express the dissent of this Government from the position which seems to be assumed by your note, that that temporary absence impairs the blockade and renders necessary a new notice of its existence. This Government holds that the blockade took effect at Charleston on the 11th day of this month, and that it will continually be in effect until notice of its relinquishment shall be given by Proclamation of the President of the United States.” On May 13th the British ship _Perthshire_ appeared off Pensacola, having heard nothing of the blockade there, but she was told that Mobile was open. So she went to Mobile, loaded cotton, and sailed on the 30th, although the port was closed on the 26th by the _Powhatan_. She was captured at sea on June 9th, by the _Massachusetts_, but released by the flagship _Niagara_, whose captain “considered the capture illegal, as, by order of the Department, no neutral vessel not having on board contraband of war was to be detained or captured unless attempting to leave or enter a blockaded port after the notification of blockade had been indorsed on her register,” The owner made a claim for £200 compensation on account of the detention of his ship, which had lost twelve days of her voyage; and the claim was allowed and paid by the government of the United States.