Punch holes at the top edge of a thin 8" square pan and lace about 7 strings from one side to the other. Place the laced pan in a pan deep enough to catch any leaking syrup. Dissolve sugar in water and cook without stirring to about hard ball stage (247-252 degrees). Pour syrup into laced pan. It should reach a level about 3/4" above the strings. Cover the surface with a piece of foil. Watch and wait. The syrup sometimes takes a week to crystallize. Lift out the laced pan. Cut the strings and dislodge the rock candy. Rinse quickly in cold water and put on racks in a very low oven to dry.