This map is a nautical chart showing the topography and hydrography of the area in Texas around the San Luis Pass. The physical features are in color and appear to be shaded to portray heights (additional relief shown by hachures). Depths are marked with lines and numbers in feet. According to text at the bottom of the page, the various measurements to create the map were made between 1851 and 1853; the text also gives specific latitude and longitude of the area in the map. Additional text in the lower right corner is labeled "Sailing Directions" and "Tidal Remarks"; the text gives explanatory details regarding the markings and measurements on the map. Scale 1:20,000. Prime meridian: Greenwich.