The jury to whom a case has been submitted may be discharged by the court when they cannot agree and the parties consent to their discharge, or when they have been kept together for such time as to render it altogether improbable that they can agree, or when any calamity or accident may, in the opinion of the court, require it, or when by sickness or other cause their number is reduced below the number constituting the jury in such court.
The cause shall again be placed on the jury docket and shall again be set for trial as the court directs.
Tex. R. Civ. P. 289