TXDOT photographs of courthouses

Fortunately for us, an unknown photographer (or photographers, we don't know) traveled the state in the late 1930's and photogaphed almost all of the courthouses.  I imagine this photographer(s) was probably the first to document the Texas courthouses as a group.  These photographs thankfully found their way to the TXDOT library in Austin.  Here they were eventually scanned and made available to persons like myself.  The collection is dated 1939 but it's diffcult to believe they were all taken in that one year.  There is speculation these photos were associated with the 1936 Texas Centennial, but that hasn't been confirmed.  On the other hand, the Sterling County courthouse of 1938 is among the photos in the collection so that one couldn't have been taken in 1936.
In addition to these so-called 1939 photos, I was given digital files of a series of scrapbooks which include photographs of some courthouses, along with TXDOT related buildings and roads.  Best of all, the photos are labeled!  These scrapbooks have yielded some additional courthouse photos.  For example, this afternoon I found a rare photo of the 1905 Sterling County courthouse, which is now included in this website.  There is very little information about this 1905 courthouse building.  The usual source, the Texas Historical Commission, doesn't offer much:  no architect or builder names for example.  This photo is the only image I've found.