The question has been raised, how many surviving brick roundhouses still standing in Califonria? Perhaps a more pertinent questin is how many roundhousese of any type are still extant in California - darn few I bet. San Jose is on a pallet, of course. Sacramento is just brick footings. Last I heard the Santa Barbara roundhouse (stucco over unknown structure) was still standing as a warehouse. Jamestown is of course wood frame with corrugated metal. Off the top of my head, I don't recall any other surviving roundhouses in California, brick or otherwise, but probably it's worth checking further.