Clausel, always venturesome, was inclined at first to go on with his enterprise, when news reached him that Bilbao, which he had left rather weakly garrisoned, was threatened by the guerrillero Jauregui, and the battalions of the volunteers of Biscay and Guipuzcoa. He returned hastily to his head-quarters with his French battalion, but found that the danger had been exaggerated for the moment, so sent out General Rouget with two battalions to join Palombini, who had meanwhile on the 24th fought a severe action with Mendizabal. The Spaniard had tried to surround him in his camp at San Pelayo, with several outflanking columns--the Italian sallied out and drove him off with loss--but suffered himself no less[392]. Clausel, on reaching the front, came to the conclusion that Castro must not be attacked without heavy guns and a larger field-force. He directed Palombini to burn the ladders, fascines, &c., prepared for the assault, and to go off instead to raise the blockade of Santoña, while he himself returned to Bilbao. The Italian division therefore marched westward on Colindres, on the other side of the bay on which Santoña stands, thrusting aside the Spanish blockading forces, and communicated with the governor, General Lameth. A supply of small arms and ammunition, money, and food was thrown into the place. On the other hand, Lameth was ordered to get six heavy guns on shipboard, and to be prepared to run them down the coast, when next a French force should appear in front of Castro-Urdiales, along with a provision of round shot, shells, and entrenching tools. Lameth got the siege material ready, but was not asked for it till another full month had gone by, for Clausel had other business pressed upon him.