6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



the tree-ring calendar back to A. D. 700. Beam HH-39, found at 

 Showlow, proved to be the key beam that converted the relative dating 

 series of more than 580 years into the absolute chronology by con- 

 firming what was found to be a short over-lap instead of a gap. The 

 outer rings of the specimen in question could be read to about A. D. 

 1380, while its central ring dated A. D. 1237. The innermost rings 

 coincided with the last rings of the prehistoric chronology and the outer 

 rings were readily identifiable with the 13th and 14th century records 

 of the historic sequence. Subsequent excavations yielded additional 

 timbers which covered practically the same period, thus substantiating 

 the record of the key log and relieving all feeling of uncertainty that 

 might accompany the placing of so much reliance on a single beam. 



The relation of tree-ring studies to archeology is obvious with the 

 realization that beams showing true outsides found in ancient dwellings 

 will not only give the cutting date of the timber, but will also strike 

 near the time of the construction of the dwelling. Eventually we may 

 be able to interpret the entire development of Pueblo architecture in 

 terms of actual dates and even trace minor changes of architecture 

 within a single pueblo. Needless to say, the artifacts associated with 

 dated ruins become more instructive in view of the added data con- 

 cerning their antiquity. 



The future of tree-ring research as applied to archeology is ex- 

 tremely promising. The present status of the study, which has enabled 

 the dating of approximately 40 pre-Spanish ruins, is the bare beginning 

 of what will eventually be accomplished. There remains yet the dating 

 of many ruins which have escaped thorough investigation ; the back- 

 ward extension of the tree-ring calendar beyond the present terminal 

 date of A. D. 700, so that structures older than Pueblo Bonito may be 

 assigned to their respective places in the scale of development ; and the 

 dating of the many impressive ruins in the Rio Grande drainage, New 

 Mexico, which, as yet, have gone undated. Other phases of the prob- 

 lem, now unthought of, are certain to follow. 



In the following report, an attempt is made to correlate the archeo- 

 logical observations derived incidental to the search for charcoal with 

 the data obtained from the charcoal specimens themselves. For the 

 use of the latter information I am deeply obligated to Doctor Douglass. 

 In view of the rather limited excavations, it is desirable to point out the 

 trend of cultural development in the region under consideration rather 

 than to venture many positive conclusions. Furthermore, it is too early 

 yet to speak with finality concerning the complete relations of the 

 datable charcoal to the ruins, for that depends upon continued research. 



