Dendrochronology (from Greek, dendron, "tree";, khronos, "time"; and, -logia) or tree-ring dating's the method of scientific dating based on the analysis of tree-ring growth patterns. This technique was developed during the first half of the 20th century originally by the astronomer A. E. Douglass, the founder of the Laboratory of Tree-Ring Research at the University of Arizona. Douglass sought to better understand cycles of sunspot activity and reasoned (correctly) that changes in solar activi… (More on Dendrochronology)