Texas, Muster Roll Index Cards, 1838-1900
This database contains index cards with details extracted from various rolls related to Texas military ... Texas Rangers, Republic Rangers, Texas Navy, Texas ...
search.ancestry.com/search/db.aspx?dbid=2059 - Cached
Try this. I could not find an officer JW Clark but several privates. You may also have to check every name that starts with a J or even a W. If you are positive its a clear JW Clark on the saddlebag. This may take awhile but is do-able.
Tally ho!