40.25 by 38.75 inches framed. - 31.25 by 27.75 inches unframed.

Until a well developed system of railroads was completed in the late 1800s, access by Texans to the seacoast of the Gulf of Mexico was crucial to the success of virtually every enterprise in the state.  Ships were sailing from – and in between – various Texas ports connected to New Orleans and then onwards to the east coast. The only alternative travel was by dirt wagon road to northwest Louisiana which connected to a riverboat that descended the Red River to the Mississippi.

Immediately after the Republic of Texas joined the United States in 1845, efforts began to make accurate triangulated charts of the entire coastline by the engineers, topographers and hydrographers of the U.S. Navy’s Coastal Survey Office.

The first surveys were of the important commercial centers - most notably Galveston and Galveston Bay. Fine charts which included detailed information on tides as well as sailing instructions were finished in the early 1850s.  Other surveys followed, including those for Indianola (which was a strong commercial rival to Galveston) and Port Lavaca (also near present day Corpus Christi), as well as preliminary surveys at Velasco at the mouth of the Brazos and Port Isabelle at the mouth of the Rio Grande

Work on the uninhabited regions between these ports began again after the end of the War Between the States and the complete survey was finished in 1875, but work continued on until the early 1900s.