Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society to Professor Alfred William Porter FRS 'With reference to your letter of March 15, the cheque which you enclosed for your annual contribution is made out for £3.3, but the amount due is three pounds only. I return the cheque herewith. If you will alter the sum to the lesser figure, initialling the alterations, and send the cheque back to me, it can be paid to Bank.' 15 March 1915