Sift together flour, dash salt and baking powder. Pour 1 cup of boiling water over dates and add 1 tsp baking soda and let cool. Cream butter and sugar well. Add eggs and beat again. Add vanilla. Add flour mixture alternatively with the date mixture into creamed butter. Beat well and add nuts. Pour into greased loaf pan and bake at 300°F for 1 hour and 10 minutes. Let cool 10 minutes before removing from pan.