In the meantime another collision still more serious had occurred with the treaty powers. The daimyō of Chōshū had, as we have seen, taken sides with the court of Kyōto against the more liberal policy of the shōgun’s government. He had placed men-of-war as guards and had erected batteries within his territory on the shores of the Shimonoseki straits through which ships usually passed on their way to and from the western ports. It is claimed, and is not improbable, that he was encouraged by the Kyōto statesmen to attack foreign ships on their way through these narrow straits, in order to embroil the Yedo government with the treaty powers. Accordingly on the 25th of June, 1863 the _Pembroke_, a small American merchant steamer on her way from Yokohama to Nagasaki was fired upon by two men-of-war belonging to the daimyō of Chōshū. She was not hit or hurt and escaped through the Bungo channel without injury. Shortly afterwards, on the 8th of July, the French gunboat _Kienchang_ while at anchor in the straits, was also fired upon and severely injured. And lastly the Dutch ship-of-war _Medusa_, in spite of a warning from the _Kienchang_, undertook to pass the straits and was fired upon by the ships and batteries of the daimyō of Chōshū, to which she responded with decisive effect. News of these hostile acts was brought immediately to Yokohama. The U. S. Steamship _Wyoming_ was lying there, and was at once despatched to avenge the insult to the American flag. She arrived at Shimonoseki on July 16th, and in a conflict with ships and batteries sunk a brig and exploded the boiler of a steamer. On the 20th inst. the French frigate _Semiramis_ and the gunboat _Tancrede_ under the command of Admiral Juares arrived to exact vengeance for the attack on the _Kienchang_. One of the batteries was silenced, and a force of two hundred and fifty men were landed who destroyed what remained. These acts of signal vengeance were followed by negotiations for damages. The shōgun’s government disavowed the actions of their rebellious subordinate; but this did not free them from responsibility for the injuries which he had inflicted. The American minister secured the payment of twelve thousand dollars for alleged losses by the _Pembroke_, although as we have seen the vessel got off without any damage. Negotiations in regard to freeing the Inland sea from obstructions dragged along for almost a year. The _bakufu_ promised to take measures to reduce to a peaceful attitude the daimyō of Chōshū whose territories bordered on the narrow straits of Shimonoseki. But the growing political disturbances of the nation and the impoverishment of the shōgun’s treasury made it impossible to carry out its pacific designs.