He served briefly as a customs inspector at Velasco while he pursued a commission in the fledgling navy of the republic, which at that time was under the command of Edwin Moore and consisted of three vessels. Tod was appointed a naval inspector in 1838, charged with investigating supply purchases at the Galveston naval station, and from 1838 to 1840 was one of the Texas Navy's purchasing agents in Baltimore. In that capacity he oversaw the construction and outfitting of the ships that became known as the "second navy." In July 1839 he was appointed a commander in the navy and the following year was placed in command of the naval station at Galveston. From November to December of 1840 he also served as acting secretary of the navy. In 1842, in the midst of controversy over the faltering navy's finances, Tod resigned his post and went to Washington to further his own interests and to act as a lobbyist for the republic. Among other issues he lobbied the state department for annexation, although he apparently was not acting in any official capacity. In 1845 he returned to Texas carrying the official notification of annexation.
During the Mexican War Tod served in the United States Navy and as an agent of the United States quartermaster general at the Brazos Santiago Depot and at New Orleans. Among other duties, he superintended the recommissioning of old Texas Navy vessels for United States service. In 1847 he resigned from the service and set out for Mexico, hoping to find some profitable business. He tried but failed to win the government mail contract for the New Orleans-Veracruz line. He returned to the United States in 1849. During the late 1840s Tod also began corresponding with Sidney Sherman over the need for railroads in Texas. By 1852 Sherman and Tod, together with eastern capitalists including John Barrett and John Angier of Boston, had founded the Buffalo Bayou, Brazos and Colorado Railway. Tod remained a principal in the company until the late 1860s. He served intermittently as treasurer and, as one of the few local shareholders, helped oversee construction and operation of the railroad.
In 1851 he was appointed the Texas delegate to the London Industrial Exhibition. He served as assistant state engineer and river-work superintendent in 1857 and for two years supervised improvements on the Guadalupe and Colorado rivers. Just before the Civil War Tod worked for the federal government as assistant superintendent of construction of the Galveston customhouse and post office. During this time he also began to develop several business interests along Dickinson Bayou in Galveston County. His Dickinson Packery, financed initially with money from a northern partner, continued to operate on a limited basis throughout the Civil War, even supplying beef to the Confederate Army. After the war the business prospered for a while, but was bankrupt by 1871. Tod married Abigail Fisher West of Delaware on July 1, 1851, in Baltimore; they were the parents of three children. They lived in Galveston, Houston, and Richmond before moving to Harrisburg in 1866. Tod died at Harrisburg on August 14, 1877, and was buried in the family cemetery there.
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