Sift the flour, baking powder and salt into a basin. Rub in the lard. Make a well in the centre of the mixture. Cream the yeast with a little warm milk, and leave to stand for five minutes. Add to the flour mixture and then add the remaining warm milk. Mix to a soft dough. Divide into four pieces and roll these out in circles half an inch thick. Put on to a greased baking sheet and bake at 375°F, 190°C, gas mark 5 for thirty minutes. While still hot, split and butter thickly.