Granular Tower (IMAGE) American Physical Society Caption Dripping a mixture of sand and water onto an absorbent surface can lead to striking structures of a wide variety of striking forms. Credit Image courtesy of Julien Chopin and Arshad Kudrolli Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.