Mighty was the straining of those three ghouls at the stone of the door above them, and Carter helped push with as much strength as he had. They judged the edge next the top of the staircase to be the right one, and to this they bent all the force of their disreputably nourished muscles. After a few moments a crack of light appeared; and Carter, to whom that task had been entrusted, slipped the end of the old gravestone in the aperture. There now ensued a mighty heaving; but progress was very slow, and they had of course to return to their first position every time they failed to turn the slab and prop the portal open.