The testimony of all witnesses examined upon an inquest shall be taken down in writing by the coroner and signed by the witnesses. If the testimony given tends to incriminate any person as concerned in the death of the deceased the coroner shall bind over the witness who gave it, in recognizance, with sufficient surety, to appear at the next court of general sessions to be holden for the county to give evidence concerning the death and such witness, for refusing to enter into such recognizance, shall be committed by the coroner to the jail of the county, by warrant under his hand and seal, there to be kept until the session of the court or until he shall enter into recognizance as required.