It became, therefore, highly important for the Americans to ascertain the state of affairs at Leon. Hence as soon as the mails for California and the Atlantic States had been despatched, Walker determined to repair to the Occidental Department. The events which transpired at Leon in consequence of that visit present another and a new phase of the war in Nicaragua. Chapter Seventh. THE DEFECTION OF RIVAS. One of the avowed objects of Jerez in desiring the Provisional President to remove to Leon was to establish friendly relations with the states to the north and particularly with San Salvador. Accordingly, even before the departure of Rivas from Granada, commissioners were sent to Cojutepeque for the purpose of explaining to the cabinet of San Salvador the actual condition of affairs in Nicaragua. But the commissioners met with a cold reception; and on the 7th of May the government of San Salvador sent a communication to the Provisional President declaring that the presence of the Americans in Nicaragua threatened the independence of Central America. The tone of the communication was so insulting that D. Patricio Rivas refused to make any reply. After, however, the retreat of the Costa Ricans from Rivas was known at Cojutepeque the news from San Salvador became more pacific; but soon came news that Guatemala was preparing troops to march against Nicaragua. So frequent and so circumstantial did these reports become, that on the 3d of June Rivas published a proclamation to the people declaring that the troops of Carrera were marching against the State, and calling on all to take up arms for the Republic. On the 31st of May, Walker, accompanied by Lieutenant-Colonel Anderson in command of two hundred Rifles, and by Captain Waters with two companies of Rangers, left Granada for Leon; and Gen. Goicouria, who fancied he understood native character because he spoke Spanish, joined the general-in-chief in the excursion to the north. Not far from Masaya the party was met by D. Mariano Salazar, who came to inform Walker of the authenticity of the reports from Guatemala and of the necessity for a portion of the American force to protect the northern frontier. Salazar represented that the people of the Occidental Department were bitter in their hostility to the troops of Carrera and might be depended on for resisting their entrance into the State; but as the Guatemalan force was said to be large and well organized, it was necessary to have some of the Rifles at Leon ready to meet it.