37. In the investigation of any claim submitted to them, the arbitrators shall cause all legal evidence offered on either side to be taken down in writing, and shall make a list of all plans, receipts, vouchers, documents and other papers which may have been produced before them during such investigation; but they may, with the consent in writing of the Minister and of the opposite party, take the evidence orally of the witnesses produced on either side, without reducing it to writing.
R. S. 1964, c. 138, s. 37.