Next Dr. Douglass began to examine beams from prehistoric sites. From these a continuous sequence of tree-ring patterns was established for a period of 580 years. Unfortunately though, it could not be correlated with the sequence starting in 1280. Relative dates could be obtained and it could be determined how many years had intervened between the occupation of different sites but there was as yet no way of correlating these dates with the Christian calendar. The next step was to seek to bridge the gap between the floating chronology of relative dates and that which carried up to the present day and gave absolute dates. The search for the missing sequence was begun in the Hopi villages in Arizona where one, Oraibi, has been continuously occupied since before the coming of the first white men in 1540. The fact that many of the logs had been cut with stone axes indicated a considerable age. The Hopis, as might be expected, were not overly enthusiastic about the arrival of American scientists who wanted to saw cross-sections from the beams of their buildings and bore holes in other timbers where cutting was not practical. Dr. Douglass did much to solve this problem by presenting the chief with yards and yards of beautiful purple chiffon velvet which delighted him. Dr. Douglass and his associates also did a great deal to mollify the Indians by treating their ancient customs with respect. In many cases, for example, they placed bits of turquoise in holes made in extracting cores in order to “appease the spirit of decay”. One remarkable piece of timber was found which gave an extraordinarily clear series of rings from 1260 to 1344. What made it of particular interest was not only that it lengthened the known chronology but that it had been in continuous use from the time it was cut until 1906 when the section of the village in which it was found was abandoned. Many beams were studied, but no others were found whose inner rings predated 1300. The search was next begun in ruins of villages traditionally occupied by the Hopis prior to moving to their present location. Of particular interest was the Showlow ruin, for pottery finds suggested that it had been the home of Hopis in pre-Spanish times and its proximity to a great pine forest suggested that wood must have been readily available for building purposes. It was here that one of the most famous pieces of wood in the world was found.