a breeze swayed the pine boughs far above , the bows slightly twisted the pine trunks at their attachment point , the trunks tilted ever so slightly all the way to the ground and moved the hooks thatd been screwed into the trunks to hold the hammock , the metal hooks grated against the metal of the grommets at either end of the hammocks cotton cords , the metal grinding against metal made a slight creak as it caused the hammock holding laura to sway ever so slightly .