Want to know about the "Texas Ethos"? The best source I’ve found, and it should be required reading at least SOMEWHERE, is Lone Star, A History of Texas and the Texans by T.R. Fehrenbach. It is still in print and has even been recently updated and revised, by the original author. The copy I have is a later (not current) printing and runs to 761 pages including the bibliography and index. So far, this is the best Texas history book I've found. It is often considered the authoritative text on the subject.