The Commercial Base Ball Club was organized on Thursday evening and the following officers elected: W.W. Sanford, President; B. Davidson, Vice-President; Eugene Karst, Secretary and Treasurer. Directors-David Hutcheson, John Cross, John Scott. The ground selected is on Ham street, between Chouteau avenue and Hickory street. The Club will play on Tuesday and Friday evenings at 5 o'clock, and Thursday mornings at 4 1/2 o'clock.
-St. Louis Daily Bulletin, June 16, 1860
Edmund Tobias, who before joining the Empire Club was a member of the Commercial Club, wrote that the Commercials were one of the first clubs formed in St. Louis and that the club was made up of young businessmen. The club broke up when Sanford took a commission in the army at the outbreak of the Civil War.
This is also the only contemporary reference that I've found to the Ham Street Grounds. According to Tobias, the grounds were used by the Cyclones, the Commercials, and the Unions during the antebellum era.