How to decipher Texas land records?

I have a record of a relative, Mathias Kabella, buying 125 acres of  along or near the San Bernardo River, near Cat Spring, Tex. in 1857. Source is Austin County of Register of Deeds. I'd like to know exactly where? The survey description is clear as mud. The Reg. of Deeds says they have no other info. I could use help from someone who knows how to read survey language in Texas land records circa 1850; or knows someone who does; or can point me in the right direction. This is the link for the search query for KABELLA, MATHIAS. He bought from JOHN P.  OSTERHOUT. https://ava.fidlar.com/TXAustin/AvaWeb/#/search. Thanks! (Texas Land Office says it does not have such information either, and plat maps I dug up from them, from this period, appear to provide names only of original land owners.)