Biography: Discovered a correlation between tree rings and sunspot cycles leading to the establishment of dendrochronology which is the dating of past events by counting and analyzing tree rings.
Douglass also helped found Lowell Observatory in 1894.
- 1919-05-22 A. E. Douglass establishes the relative dates of two archaeological sites using ancient wood samples, marking a major step forward in the dating of archaeological sites
- Book-Review - Tree Rings and Telescopes - the Scientific Career of A.E. Douglass - Journal for the History of Astronomy