Replica pipes (image) Washington State University Share Print E-Mail Caption Replica pipes used to experimentally "smoke" tobacco and other native plants in WSU laboratories for the study. The charred residue is then extracted, chemically "fingerprinted", and compared to residue of ancient archaeological pipes. Credit WSU Usage Restrictions None Share Print E-Mail 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.