About the beginning of the last week in May the Turks were alarmed by the rumour of an approaching fleet and of an army of Hungarians under John Hunyadi, both of which were reported to be on their way to the relief of the city.[362] The alarm, however, proved to be false. As Phrantzes laments, no Christian prince sent a man or a penny to the aid of the city.[363] At first sight it is somewhat surprising that no aid came either from the Serbians or Hungarians. During the early days of the siege assistance had been hoped for from both of these peoples. Phrantzes states that the despot of Serbia, George Brancovich, treated the sultan in such a manner as to make Mahomet taunt the Christians with his hostility to Constantine.[364] With the recollection of the Turkish victories at Varna and at Cossovo-pol, and especially of the fact that he had himself been attacked because he would not join in violating the peace between Ladislaus and Murad, it is probable enough that Brancovich was not unfriendly towards Mahomet. Indeed, at the request of the young sultan, he had used his influence to bring about a three years’ armistice between the Turks and the Hungarians. It is not, therefore, surprising that no aid came from him. More success might have been anticipated from negotiations with Hungary. Here, however, the three years’ agreement (made eighteen months before the siege) for an armistice stood in the way. The Hungarians had received a terrible lesson--at Varna--on the breaking of treaties, and they hesitated before violating the new arrangement. Ducas and Phrantzes agree in stating that the agents of Hunyadi had come to the city in the early days of the siege and had requested the sultan, on behalf of their principal, to give back the copy of the armistice signed by him in return for that signed by Mahomet. They gave as a pretext that Hunyadi was no longer viceroy of the king of Hungary. The design was too transparent to be accepted by the Turks.[365] The idea was to suggest to the sultan that the Hungarians were coming to the aid of the city; that they had compunctions about breaking the treaty, but that, as it was not signed by the prince, they had a valid excuse for so doing. To this extent what was done indicated a spirit friendly to the besieged. The sultan and his council promised to consider the proposition, and put the agents of Hunyadi off with a civil and banal reply.[366] Ducas tells a story regarding the visits of the agents of Hunyadi which may be noticed, though he is careful to give it as hearsay. He says that the officers in their suite showed the gunners how they might use their great bombard more effectually to destroy the walls by directing their fire in succession against two points instead of one, so as to form a triangle, and that the device succeeded to such an extent that the tower near the Romanus Gate and a part of the wall on each side of it was so broken down that the besiegers and besieged could see each other.[367]