American Military History, Volume 1

Taylor's plan was to move on Monterrey with about 6,000 men via Camargo, a small town on the San Juan River, a tributary of the Rio Grande about 130 miles upriver. From Camargo, where he intended to set up a supply base, a road led southwest about 125 miles to Monterrey in the foothills of the Sierra Madres. His troops were to march overland to Camargo, his supplies to come by steamboat up the Rio Grande. But he could not move immediately because he lacked transportation-partly because of his failure to requisition in time and partly because of the effort required to build more wagons in the United States and to collect shallow-draft steamboats at river towns on the Mississippi and the Ohio and send them across the Gulf of Mexico. Ten steamboats were in operation at the end of July, but wagons did not begin arriving until November, after the campaign was over. To supplement his wagon train, reduced to 175, Taylor had to rely on 1,500 Mexican pack mules and a few native oxcarts.

In manpower Taylor had an embarrassment of riches. May saw the arrival of the first of the three-month militia he had requested on April 26 from the governors of Texas and Louisiana. With them came thousands of additional six-month volunteers from neighboring states recruited by Bvt. Maj. Gen. Edmund P. Gaines, commander of the Department of the West, on his own initiative-a repetition of his impulsive actions during the Second Seminole War. More than 8,000 of these short-term volunteers were sent before Gaines was censured by a court-martial for his unauthorized and illegal recruiting practices and transferred to New York to command the Department of the East. Very few of his recruits had agreed to serve for twelve months. All the rest were sent home without performing any service; in the meantime they had to be fed, sheltered, and transported. In June the volunteers authorized by Congress began pouring into Point Isabel and were quartered in a string of camps along the Rio Grande as far as Matamoros.