Randy is right about the identity of the folks you mention. The Fremantle diary is very entertaining in its discussion of the characters around Houston and Galveston. I thought this part was pretty funny about Fremantle's ride down from Houston to Galveston on the train:

"In the cars I was introduced to General Samuel Houston, the founder of Texan Independence. He told me he was born in Virginia seventy years ago, that he was United States Senator at thirty, and Governor of Tennessee at thirty-six. He emigrated into Texas in 1832; headed the revolt of Texas, and defeated the Mexicans at San Jacinto in 1836. He then became President of the Republic of Texas, which he annexed to the United States in 1845. As Governor of the State in 1860, he had opposed the secession movement, and was deposed. Though evidently a remarkable and clever man, he is extremely egotistical and vain, and much disappointed at having to subside from his former grandeur. The town of Houston is named after him. In appearance he is a tall, handsome old man, much given to chewing tobacco, and blowing his nose with his fingers.

I was also introduced to another "character," Capt. Chubb, who told me he was a Yankee by birth, and served as coxswain to the United States ship Java in 1827. He was afterwards imprisoned at Boston on suspicion of being engaged in the slave trade; but he escaped. At the beginning of this war he was captured by the Yankees, when he was in command of the Confederate States steamer Royal Yacht, and taken to New York in chains, where he was condemned to be hung as a pirate; but he was eventually exchanged. I was afterwards told that the slave-trading escapade of which he was accused consisted in his having hired a colored crew at Boston, and then coolly selling them at Galveston."

[Thomas Chubb's house still stands in Galveston at 1417 Sealy. While in Galveston, Fremantle visited the "observatory", which was on top of the Hendley Building, which still stands at 20th & Strand. There are a number of photographs taken in 1861 from that observatory that are in the collection of the Rosenberg Library.]