The verdict of the jury, whether the jury are unanimous or not, shall be returned orally by the foreman of the jury unless the court shall direct a written verdict to be returned:

Provided that where the jury are not unanimous in their verdict, the foreman shall announce that fact so that the relative entry may be made in the record; and provided also that after the jury are enclosed, none of the jurors shall be allowed to separate or to hold communication with other persons until their verdict shall have been returned in their presence by the foreman.