Provided that where a cheque is presented for payment which does not, at the time of presentment, appear to be crossed, or to have had a crossing which has been obliterated, or to have been added to or altered, otherwise than as authorised hereby, the banker paying the cheque in good faith and without negligence shall not be responsible or incur any liability, nor shall the payment be questioned by reason of the cheque having been crossed, or of the crossing having been obliterated or having been added to or altered otherwise than as hereby authorised and of payment having been made otherwise than to a banker or to the banker to whom the cheque is or was crossed, or to his or agent for collection being a banker, as the case may be.