Henningsen's wife, with the spirit of a Roman matron, acquiesced heroically when her knight volunteered to go forth and do battle for a cause which would have won his sympathy for its very danger alone. His reputation as a soldier was well established. He had introduced the Miniê rifle into the United States service, and was an authority upon his speciality, the use of artillery. Nor did he come empty-handed to Nicaragua; but brought with him military stores, arms, and ammunition, to the value of thirty thousand dollars, the contribution of himself and his wife, besides an equally liberal offering from George Law and other sympathizers with the cause. Walker immediately placed him on active service, with the rank of brigadier-general. Henningsen had scarcely assumed his command before he was sent to clear the Transit road of marauding bands of Costa Ricans, a large body of whom had landed at San Juan del Sur, under General Cañas. Henningsen scattered them promptly, and admitted a force of recruits from California, who had arrived on the steamer _Cortes_. The reappearance of the Costa Ricans on the Transit was too dangerous a menace to the communication with the United States, however; and Walker saw that to preserve his base of supplies, and at the same time to garrison the large city of Granada, was a task too serious for his slender forces. But as he did not wish to let the latter important stronghold fall into hostile hands, with the moral and material benefits accruing from the possession of the seat of government, he resolved to destroy the city. Previous to evacuating Granada he made another attack on Masaya, in order that the enemy might remain on the defensive and not suspect his intended movement of retreat southward. A trifling engagement took place, in which the artillery was well handled. On the 19th of November the sick and wounded were transported in the lake steamer to the island of Omotepe, where they were placed in charge of Colonel Fry and a corps of medical attendants.