provide a coffin for each corpse, so somebody invented a coffin, the bottom of which, could be opened by means of hinges. When a corpse was taken to be buried, the coffin was placed over the grave, the hinges were undone, and the remains dropped into the grave. In this way, the same coffin was used over and over again.
Very often too, when whole families died in their homes, the neighbours gathered and simply threw the little cabin on top of them. They never had any other burial. Their little homes became their tomb.