GGG GF ALEXANDER THOMPSON, b. Rhinebeck, Duthcess Co. NY ca 1797-99. Was Midshipman aboard the US Frigate Constellation in Oct 1816. Left U.S.N. to join the Mexican Navy in 1826, and left the Mexican Navy in 1829 to join the TEXAS Navy prior to the TX Revolution. Was named Chief Cartographer of the Republic of TX in 1837. Died before Dec 10, 1839 in Montgomery Co. TX. Looking for parents and/or siblings and/or anyone connected to him in NY. He may have been related to Henry Livingston Thompson - they followed the same path thru the navies and both lived in the same area of TX. Have info and will share. Any help appreciated. Thanks! Joanne