Put the dtaes in a bowl and stir in the bicarbonate of soda and boiling water. Leave to soak until required. Sift the flour and salt into a bowl. In another bowl cream together the margarine, sugar and syrup. Beat the egg into the creamed mixture, then add the flour, walnuts and date mixture and mix well. Divide between two greased and lined 1lb loaf tins and bake in a preheated cool oven(300F) for 1hr.15 min.