... Making a Sand Clock and a Water Clock The Sand Clock Materials: Two small, plastic bottles (e.g. 16-32 oz. soda bottles); sand; masking or ducttape, 1"X 1" square of thick aluminum foil; sharp pencil; wristwatch or classroom clock for calibration ...
... Materials: Two small, plastic bottles (e.g. 16-32 oz. soda bottles); sand or salt; masking or ducttape, 1"X 1" square of thick aluminum foil; sharp pencil; wristwatch or classroom clock for calibration. ...